Add pages (grammar)

src/grammar/misplaced_modifiers.md

@@ -1 +1,62 @@
 # Misplaced Modifiers
+
+
+
+Modifiers should be placed next to the words they modify, and any exception to the rule can produce ambiguity or even a complete lack of clarity.
+
+```example
+Incorrect: "While hunting in Africa, I shot an elephant in my pajamas. How an elephant got into my pajamas I'll never know." (Groucho Marx in Animal Crackers, 1930)
+```
+
+
+
+The main problem with the misplaced modifier is that the person reading the sentence may misinterpret the meaning.
+
+In the sentence above, the phrase in my pajamas has been placed at the end of the sentence, apparently modifying the word elephant rather than in the beginning, where it would modify the subject I.
+
+A less ambiguous, and sadly humorless, version of Groucho's sentence would be:
+
+```example
+Correct: "While hunting in my pajamas in Africa, I shot an elephant."
+```
+
+
+> **Rule To Remember**
+>
+> Modifiers should be placed next to the words they modify to avoid ambiguity in sentences.
+
+## Correcting Misplaced Modifiers
+
+To correct the misplaced modifier problem, one should place single word adjectives before the word they modify and adjective phrases or clauses right after the word they modify.
+
+In the following examples, adjective phrases were placed right after the word they modify to avoid ambiguity.
+
+```example
+Incorrect: The suspects were interviewed right after the crime was committed by the detectives.
+```
+
+
+```example
+Correct: The suspects were interviewed by the detectives right after the crime was committed.
+```
+
+
+```example
+Incorrect: John was praised for his great accomplishments by his teacher.
+```
+
+
+```example
+Correct: The teacher praised John for his great accomplishments.
+```
+
+
+```example
+Incorrect: The student walked her dog in blue sweatpants.
+```
+
+
+```example
+Correct: The student in blue sweatpants walked her dog.
+```
+

src/grammar/parallelism.md

@@ -1 +1,127 @@
 # Parallelism
+
+
+Conjoined items in a sentence must be in the same grammatical form.
+
+```example
+Incorrect: I like to jog and walking.
+```
+
+
+In the above sentence, to jog and walking are not parallel in grammatical
+construction.
+
+Parallelism is the matching of the forms of words, phrases, or clauses within a
+sentence. Editing your work for parallel construction improves clarity and
+emphasizes your points.
+
+> **Rule To Remember**
+>
+> Conjoined items in a sentence must be in the same grammatical form,
+> i.e. grammatically parallel.  Correcting Faulty Parallelism
+
+To avoid faulty parallelism, the sentence above should be corrected to:
+
+```example
+Correct: I like jogging and walking.
+```
+
+
+Words, phrases, and clauses joined by a coordinating conjunction (and, but, or,
+nor, for, so, yet) need to have parallel grammatical construction.
+
+```example
+Incorrect: We all need good nutrition and to exercise on a regular basis.
+```
+
+
+```example
+Correct: We all need good nutrition and regular exercise.
+```
+
+
+Words, phrases, and clauses joined by a correlative conjunction (not only... but
+also, both... and, either... or, neither... nor) need to have parallel
+grammatical construction.
+
+```example
+Incorrect: like both to read books and watching movies.
+```
+
+
+```example
+Correct: like both to read books and to watch movies.
+```
+
+
+Words, phrases, and clauses joined by a comparative expression (as much as, more
+than, less than) need to have parallel grammatical construction.
+
+```example
+Incorrect: enjoy going out to a movie as much as I like to rent a movie and stay home to watch it.
+```
+
+
+```example
+Correct: enjoy going out to a movie as much as I enjoy renting a movie and staying home to watch it.
+```
+
+> **Rule To Remember**
+>
+> Items joined by a coordinating or a correlative conjunction, or by a comparative
+> expression need to be parallel in their grammatical form.
+
+In the following example, inserting because before each of the elements makes
+each point a subordinate adverbial clause and adds to the clarity of the whole
+sentence.
+
+```example
+Incorrect: Many people maintain a healthy diet because they want to look healthy, it increases their energy, and they want to live longer.
+```
+
+
+```example
+Correct: Many people maintain a healthy diet because they want to look healthy, because it increases their energy, and because they want to live longer.
+```
+
+
+Words, phrases, and clauses in a series should be parallel in grammatical
+construction.
+
+```example
+Incorrect: He is smart, honest, and has a great sense of responsibility.
+```
+
+
+```example
+Correct: He is smart, honest, and very responsible.
+```
+
+
+Items in a bulleted list should also be parallel in their grammatical form.
+
+```example
+Incorrect:
+
+Set up your own wiki:
+
+    Explore sample wiki sites
+    Creating an account on free hosting services
+    Selecting a wiki name
+    How to choose privacy options
+    Creating and customizing your wiki site
+```
+
+```example
+Correct:
+
+Set up your own wiki:
+
+    Explore sample wiki sites
+    Create an account on free hosting services
+    Select a wiki name
+    Choose privacy options
+    Create and customize your wiki site
+```
+
+

src/grammar/pronoun_agreement.md

@@ -1 +1,134 @@
 # Pronoun Agreement
+
+Pronouns must agree in number, gender, and person with their antecedents.
+
+```example
+Incorrect: Neither of my classmates are taking the trip this summer.
+```
+
+
+## Correcting Faulty Pronoun Agreement
+
+If the subject of the sentence is a pronoun, that pronoun needs to agree in number with the verb.
+
+In the sentence above, the pronoun neither is always singular, and it should take the singular form of the verb:
+
+```example
+Correct: Neither of my classmates is taking the trip this summer.
+```
+
+
+> **Rule To Remember**
+>
+> Pronouns must agree in number, in gender, and person with their antecedents.
+
+Additionally, pronouns should also agree with the antecedent in number, gender, and person.
+
+The indefinite pronoun everybody is always singular. The pronoun their which refers back to its antecedent everybody also needs to be in the singular form.
+
+```example
+Correct: Everybody has been bringing their own lunch lately.
+```
+
+
+## Agreement in Number
+
+### Indefinite Pronouns
+
+Some indefinite pronouns are always singular:
+|           |            |         |          |
+|-----------|------------|---------|----------|
+| anybody   | anything   | either  | nobody   |
+| everybody | everything | neither | someone  |
+| anyone    | another    | one     | somebody |
+| everyone  | each       | no one  |          |
+
+
+<br/>
+
+
+```example
+Correct: Neither of the best players in the last game was injured.
+```
+
+
+```example
+Correct: Anyone of the guests is welcome to participate in the raffle.
+```
+
+
+```example
+Correct: Everyone has cast his or her vote.
+```
+
+
+Some are always plural:
+|      |     |         |      |
+|------|-----|---------|------|
+| both | few | several | many |
+
+<br/>
+
+
+```example
+Correct: Few of the days this spring have been above 50 degrees.
+```
+
+
+```example
+Correct: Several of the participants shared their personal experiences.
+```
+
+
+And some can be both singular or plural depending on the kind of noun they refer to.
+
+|     |     |      |      |      |
+|-----|-----|------|------|------|
+| all | any | most | none | some |
+
+<br/>
+
+```example
+Correct: None of the food has been left after the party.
+```
+
+
+```example
+Correct: None of the players have quit the team after a difficult season.
+```
+
+
+### Relative Pronouns
+
+A relative pronoun is a pronoun that refers to a noun preceding it in the sentence. This noun is called its antecedent.
+
+Relative pronouns need to agree with their antecedents in number. If the nouns relative pronouns are referring to (antecedents) are plural, then the plural form of the verb is used, and if the noun is singular, then the singular form of the verb is needed.
+
+```example
+Correct: John was one of the players who were chosen to play in the final game.
+```
+
+
+```example
+Correct: John is the player who has scored in most of the games.
+```
+
+
+## Agreement in Gender
+
+Here most problems occur when the antecedent may be either masculine or feminine. To avoid gender bias, it is best to use their in such sentences. For example,
+
+```example
+Correct: Each faculty member of the department is encouraged to share their grant proposals with the committee.
+```
+
+
+## Agreement in Person
+
+
+A personal pronoun must also agree in person with its antecedent. Pronouns one, everyone, everybody are third person pronouns.
+
+```example
+Correct: One should carefully consider their choice of major.
+```
+

src/grammar/pronouns.md

@@ -1 +1,169 @@
 # Pronouns
+
+A pronoun is a word that can substitute for a noun or a noun phrase.
+
+There are several common types of mistakes made in pronoun usage. The most frequent mistake, involving pronoun-antecedent agreement, is covered in the [Pronoun Agreement](./pronoun_agreement.md) section of this tutorial.
+
+This particular section will cover mistakes in the use of relative, personal, and reflexive pronouns, as well as pronoun reference, and in the use of gender-neutral language.
+
+When used in questions, who is the nominative form of the pronoun, and it should be used when the pronoun is the subject.
+
+```example
+Correct: Who is finished with the first assignment? He is finished with the assignment.
+```
+
+
+Whom should be used in questions when the pronoun is the object of the verb or preposition.
+
+```example
+Correct: Whom do you like best? I like him.
+```
+
+
+```example
+Correct: Whom did you meet at the conference? I met them.
+```
+
+
+Who, whom, and whose are also used to introduce clauses. Whom should be used when the pronoun is the object of the verb in the clause or the object of the preposition. Whose expresses possession.
+
+```example
+Correct: I do not remember whom my friend recommended.
+```
+
+
+```example
+Correct: I do not remember whose recommendation it was.
+```
+
+
+```example
+Correct: John was the person who was recommended for the internship.
+```
+
+
+## Personal and Reflexive Pronouns (I, Me, Myself)
+
+
+```example
+Incorrect: The teacher asked Anne and myself to do a peer review of each other's writing.
+```
+
+
+Here, the pronoun myself is used incorrectly. Myself is a reflexive pronoun. Reflexive pronouns are used when the subject and the object are the same. It can also be used for emphasis.
+
+The sentence above should be corrected to:
+
+```example
+Correct: The teacher asked Anne and me to do a peer review of each other's writing.
+```
+
+
+Here are examples when the reflexive pronoun is used correctly:
+
+```example
+Correct: I'll do this assignment myself.
+```
+
+
+```example
+Correct: I myself was scared to go into the dark room.
+```
+
+
+Another error occurs when, instead of using the objective form of the personal pronoun (me, him, her, etc.), we use the subjective form (I, he, she, etc.).
+
+```example
+Incorrect: This peer review needs to be completed by Anne and I.
+```
+
+
+The phrase completed by requires an object, so we should use the objective form of the first person pronoun -- me.
+
+```example
+Correct: This peer review needs to be completed by Anne and me.
+```
+
+
+In order to make the sentence sound more formal, users often substitute I with myself incorrectly.
+
+```example
+Incorrect: John and myself will join you later at the reception.
+```
+
+
+In the above sentence, we should use I instead of myself. Both John and I are subjects in that sentence; therefore, the subjective form of the pronoun should be used. We certainly cannot say:
+
+```example
+Incorrect: Myself will join you later at the reception.
+```
+
+
+Here's the corrected sentence:
+
+```example
+Correct: John and I will join you later at the reception.
+```
+
+
+## Vague or Ambiguous Reference
+
+
+Vague (or no) reference to the antecedent is one of the most common errors made by writers at many levels, as is the ambiguous use of pronouns as the subjects of sentences.
+
+```example
+Ambiguous: Tina and her mother went out, even though she didn't want to.
+```
+
+
+Here it is not clear who she refers to. To correct this error, simply make it clear who she is:
+
+```example
+Preferred: Tina and her mother went out, even though Tina didn't want to.
+```
+
+
+Consider the following example:
+
+```example
+Ambiguous: Cough syrup and cold pills are cheap. This is what you can use to fight your cold most effectively.
+```
+
+
+What this refers to is vague. It could either mean the cough syrup or the pills, or even both. To make the second sentence less ambiguous, remove this and clarify. There are many possible solutions; here is one:
+
+```example
+Preferred: Cough syrup and cold pills are cheap. Patients need both to fight cold most effectively.
+```
+
+
+You should be used only when referring directly to the reader.
+
+```example
+Ambiguous: Doctors recommend that you should take multivitamins on a regular basis.
+```
+
+
+```example
+Preferred: Doctors recommend taking multivitamins on a regular basis.
+```
+
+
+```example
+Ambiguous: She sang beautifully. This made the audience cheer her.
+```
+
+
+```example
+Preferred: Her beautiful singing made the audience cheer.
+```
+
+
+## Gender-neutral Language
+
+The use of gender-neutral language, while not specifically a grammatical issue, can be an important stylistic concern.
+
+```example
+Neutral: Everyone has a preference as to what to put on a hamburger.
+```
+

src/grammar/relative_clauses.md

@@ -1 +1,210 @@
 # Relative Clauses
+
+A relative clause is a subordinate clause that modifies a noun or a nominal.
+
+```example
+Correct: The memo was sent to all instructors who were teaching Spanish 101.
+```
+
+
+```example
+Correct: The book which I borrowed from the library last semester is due this week.
+```
+
+
+```example
+Correct: Stonehenge is a prehistoric monument which was erected more than four thousand years ago.
+```
+
+> **Rule To Remember**
+>
+> A relative clause is a subordinate clause that modifies a noun or a nominal.
+
+There are two kinds of relative clauses: non-defining and defining, also called non-restrictive and restrictive. The choice of a relative pronoun depends a lot on the type of clause.
+
+## Defining Relative Clauses
+
+Defining relative clauses give essential information about the noun.
+
+When the noun modified is a person and also a subject of that clause, who is usually used.
+
+```example
+Correct: The man who robbed the bank was arrested the next day. (The man robbed the bank.)
+```
+
+
+That can be used instead of who after all, everyone, everybody, no one, nobody, those:
+
+```example
+Correct: Those who/that took a class online said they would take an online class again.
+```
+
+
+When the noun modified is a person and also an object, who, that, or whom may be used. Or the relative pronoun may be omitted.
+
+```example
+Correct: The interns whom this company employs come from a number of northern Illinois colleges and universities.
+```
+
+
+```example
+Correct: The interns who this company employs come from a number of northern Illinois colleges and universities.
+```
+
+
+```example
+Correct: The interns that this company employs come from a number of northern Illinois colleges and universities.
+```
+
+
+```example
+Correct: The interns this company employs come from a number of northern Illinois colleges and universities.
+```
+
+> **Rule To Remember**
+>
+> Defining relative clauses provide essential information about the noun or the nominal.
+
+With prepositions we can use either whom or that. The use of whom is more formal.
+
+```example
+Correct: My friend with whom I took this class has already graduated.
+```
+
+
+```example
+Correct: My friend that I took this class with has already graduated.
+```
+
+
+When the noun modified is a thing and a subject of that clause, which or that can be used. The use of which is more formal.
+
+```example
+Correct: This is the package that/which I have been waiting for.
+```
+
+
+If the relative clause modifies an object of a verb, which, that, or no relative pronoun can be used. Which is rarely used after all, everything, little, much, none, no, or after superlatives.
+
+```example
+Correct: The car which I rented last week broke down.
+```
+
+
+```example
+Correct: This is the best book I have ever read.
+```
+
+
+To express possessive, only one form is possible: whose.
+
+```example
+Correct: The man whose wife was missing was later questioned by the police.
+```
+
+> **Rule To Remember**
+>
+> Non-defining relative clauses provide non-essential or extra information about the noun or the nominal.
+
+
+## Non-defining Relative Clauses
+
+Non-defining relative clauses provide non-essential or extra information about the noun.
+
+Unlike defining relative clauses, non-defining relative clauses are separated from the noun by commas. The pronoun cannot be omitted in a non-defining relative clause.
+
+When the noun modified is a person and a subject of the clause, only the relative pronoun who can be used in non-defining relative clauses.
+
+```example
+Correct: Anne, who is an outstanding researcher, presented her paper on the health effects of air pollution at the Conference on Global Warming.
+```
+
+
+When the noun modified is a person and also an object of the clause, who or whom is used. Whom is the correct form, and it is used more in formal English. In spoken English, who is frequently possible.
+
+```example
+Incorrect: Anne, that everyone respects, was invited to speak at a conference on the health effects of air pollution.
+```
+
+
+```example
+Incorrect: Anne, which everyone respects, was invited to speak at a conference on the health effects of air pollution.
+```
+
+
+```example
+Correct: Anne, whom everyone respects, was invited to speak at a conference on the health effects of air pollution.
+```
+
+
+When the modified noun is an object of a preposition, whom is used.
+
+```example
+Correct: Anne, with whom I exchanged only casual conversation, invited me to her next meeting.
+```
+
+
+Possessive is expressed by whose.
+
+```example
+Correct: Anne, whose research on the health effects of air pollution was well-known, was invited to speak at a conference.
+```
+
+
+In non-defining relative clauses, we mostly use which to modify nouns that are either subjects, objects, or objects of a preposition.
+
+```example
+Correct: The book, which took years to write, was an instant hit.
+```
+
+
+```example
+Correct: For my birthday, she gave me a book, which she picked out herself.
+```
+
+
+## Connective Relative Clauses
+
+Connective relative clauses (one of ..., two of ..., several of ...) do not define nouns, but rather continue the story. Whom is used with persons and which with things.
+
+```example
+Correct: I introduced her to my friends, one of whom offered us a ride home.
+```
+
+
+```example
+Correct: The teacher introduced several new topics in class, one of which involved cyber security.
+```
+
+
+Whoever and whichever can mean "the one who" or "no matter who."
+
+```example
+Correct: Whoever answers the last question gets ten extra credit points.
+```
+
+
+```example
+Correct: Whichever of us answers the last question gets ten extra credit points.
+```
+
+
+```example
+Correct: I will assign this to whoever responds first.
+```
+
+
+Sometimes whoever and whomever get confused.
+
+```example
+Correct: This internship will be given to whoever does best at the interview.
+```
+
+
+```example
+Correct: This internship is for whomever we choose as the best candidate.
+```
+
+---
+
+<!-- TODO: add link to quiz -->

src/grammar/split_infinitives.md

@@ -1 +1,125 @@
 # Split Infinitives
+
+
+Split infinitives are a specific type of misplaced modifier.
+
+```example
+Incorrect: She decided to instantly quit her job.
+```
+
+
+An infinitive is a verb preceded by the word to: (to write, to examine, to take,
+to cooperate). When an adverb appears between to and the verb itself, we get a
+split infinitive.
+
+> **Rule To Remember**
+>
+> - Split infinitives are a specific type of misplaced modifier.
+> - Split infinitives should be avoided in formal writing.
+
+
+## Correcting Split Infinitive Problems
+
+To correct the above sentence, instantly should appear after the verb.
+
+```example
+Correct: She decided to quit her job instantly.
+```
+
+In formal writing, it is considered bad style to split an infinitive, but in
+more informal writing or in speech this has become more acceptable.
+
+In speech, the word really is often placed between to and the verb:
+
+```example
+Non-standard: It would take incredible strength to really forget all her bad childhood memories.
+```
+
+
+```example
+Awkward: It would take incredible strength to forget really all her bad childhood memories.
+```
+
+
+Placing really after forget makes the second sentence sound awkward. Really is
+such a problematic word, it is best to avoid its use in writing and use a more
+specific adverb.
+
+Some degree adverbs such as completely, entirely, unduly can also create awkward
+sentences when placed after the verb.
+
+```example
+Non-standard: It's hard to completely follow his reasoning.
+```
+
+
+```example
+Awkward: It's hard to follow completely his reasoning.
+```
+
+
+A better choice here would be to put the adverb completely at the very end of
+the sentence.
+
+```example
+Preferred: It's hard to follow his reasoning completely.
+```
+
+
+Sometimes avoiding the use of a split infinitive creates ambiguity. Consider the
+following examples:
+
+```example
+Non-standard: The patient was told to occasionally monitor her blood sugar level.
+```
+
+
+```example
+Correct: The patient was told occasionally to monitor her blood sugar level.
+```
+
+
+```example
+Correct: The patient was told to monitor her blood sugar level occasionally.
+```
+
+
+In the second sentence, occasionally modifies the verb told and, in fact, alters
+the meaning of the sentence. However, placing occasionally at the end of the
+sentence creates ambiguity; does it modify the verb told now or the verb
+monitor?
+
+The best position of the modifier occasionally is right after the verb monitor
+as in:
+
+```example
+Correct: The patient was told to monitor occasionally her blood sugar level.
+```
+
+
+In formal writing, sentences in which there is more than one element in the
+infinitive phrase should be avoided:
+
+```example
+Non-standard: Our company decided to legally and rightfully seek damages for fraudulent use of the company documents.
+```
+
+
+Sometimes it may be necessary to rephrase the sentence to maintain the correct
+form and meaning:
+
+```example
+Preferred: Our company decided to seek damages in a legal and rightful way for fraudulent use of the company documents.
+```
+
+
+Or
+
+```example
+Preferred: Legally and rightfully, our company decided to seek damages for fraudulent use of the company documents.
+```
+
+
+---
+
+<!-- TODO: add quiz -->

src/grammar/subject-verb_agreement.md

@@ -1 +1,181 @@
 # Subject-verb Agreement
+
+A verb must agree in person and number with its subject.
+
+```example
+Incorrect: My friend, with his parents, are flying in today to visit me and my family.
+```
+
+
+When the subject of the sentence does not agree in number with the verb, the
+sentence lacks subject-verb agreement. To preserve the subject-verb agreement,
+singular subjects take verbs marked for singular. Plural subjects must have
+verbs that are marked for plural.
+
+> **Rule To Remember**
+>
+> A verb must agree in number and in person with its subject.
+
+## Correcting Faulty Subject-verb Agreement
+
+Errors typically occur when the writer does not know whether the subject is
+singular or plural.
+
+In the sentence above, friend is the only subject and the verb are flying should
+be in singular form (is flying) to agree with it in number. The phrase with his
+parents is a prepositional phrase and not part of the subject, so it has no
+effect on the verb form.
+
+```example
+Correct: My friend, with his parents, is flying in today to visit me and my family.
+```
+
+
+Here is another example:
+
+```example
+Correct: Neither my mother nor my sisters are coming to visit me this summer.
+```
+
+
+## Subjects Followed By Prepositional Phrases
+
+
+Prepositional phrases such as with, together with, along with, as well as are
+not part of the subject and, therefore, have no effect on the form of the
+verb. The verb needs to agree in number only with the subject of the sentence.
+
+```example
+Incorrect: Laura, together with a friend, practice yoga every day.
+```
+
+
+```example
+Correct: Laura, together with a friend, practices yoga every day.
+```
+
+> **Rule To Remember**
+>
+> Compound subjects are joined by and need a plural verb.
+
+## Compound Subjects
+
+
+Compound subjects joined by and need a plural verb.
+
+```example
+Correct: Healthy diet and regular exercise are a necessity for a longer, happier life.
+```
+
+
+When the compound subject is joined by or, nor, neither... nor, either... or and
+one part of the compound subject is singular and the other part is plural, the
+verb needs to agree with the part closest to it.
+
+```example
+Incorrect: Neither students nor their teacher are participating in this play.
+```
+
+
+```example
+Correct: Neither students nor their teacher is participating in this play.
+```
+
+
+## Subjects Following Verbs
+
+If the subject is following the verb in the sentence, rather than preceding it,
+it still has to agree with it in number.
+
+```example
+Incorrect: Here's my test scores.
+```
+
+
+```example
+Correct: Here are my test scores.
+```
+
+
+## Collective Nouns
+
+
+Collective nouns which refer to a group of people or things can take either a
+singular verb or a plural one depending on the meaning that is being implied. If
+the collective noun is taken to represent the group as one whole, then the
+singular form of the verb is used. For example:
+
+```example
+Correct: The diversity committee was well represented at the last board meeting.
+```
+
+
+If individual members are implied, then the verb takes the plural form:
+
+```example
+Correct: The committee were voting on the representative to the board of directors' meeting.
+```
+
+
+```example
+Correct: The audience was cheering the performer.
+```
+
+
+```example
+Correct: When the concert ended, the audience were reluctant to leave.
+```
+
+> **Rule To Remember**
+>
+> Collective nouns which refer to a group of people or things can take either a
+> singular verb or a plural one.
+
+## Nouns With Plural Form
+
+Some nouns occur only in plural form, but they are singular nouns and take a
+singular verb: politics, news, ethics, measles.
+
+```example
+Correct: Ethics is an important component of human study.
+```
+
+
+Plural nouns of Latin origin take plural verbs (alumni, media, criteria,
+phenomena). The word data can take both a singular verb or a plural verb. The
+use of plural is more formal.
+
+```example
+Correct: Very little data was provided to substantiate the hypothesis.
+```
+
+
+```example
+Correct: The data for the study were collected from over 300 participants.
+```
+
+> **Rule To Remember**
+>
+> Collective nouns which refer to a group of people or things can take either a
+> singular verb or a plural one.
+
+## Time and Amount Nouns
+
+Subjects that express time or amount also take a singular verb.
+
+```example
+Correct: Forty thousand is an average starting salary for a Computer Science graduate.
+```
+
+
+## Titles and Country Names
+
+Titles and names of countries take the singular form of the verb.
+
+```example
+Correct: The Netherlands is a European country that borders Belgium.
+```
+
+---
+
+<!-- TODO: add quiz --

src/grammar/use_of_numbers.md

@@ -1 +1,215 @@
 # Use of Numbers
+
+
+It can be difficult knowing when to use numerals and when to spell them out.
+
+```example
+Incorrect: The book highlights major events in the 1960's in the American history.
+```
+
+
+```example
+Correct: The book highlights major events in the 1960s in the American history.
+```
+
+
+```example
+Incorrect: Students need to hand in 2 copies of their assignment.
+```
+
+
+```example
+Correct: Students need to hand in two copies of their assignment.
+```
+
+
+> **Rule To Remember**
+>
+> Spell out numbers below 10 in MLA style or below 100 in APA style.
+
+## Correcting Wrong Use of Numbers
+
+
+Numbers between 1 and 9 should be spelled out (in MLA style). When the writing sample uses numbers infrequently, or if APA style is followed, numbers between 1 and 100 should also be spelled out.
+
+If two or more related numbers are used in a sentence, one below 10 and one a bigger number, their use should be consistent. They can either be spelled out or written as numerals.
+
+```example
+Correct: We have a large family. My sister has 5 children. My great grandmother, however, had 19 grandchildren before she died.
+```
+
+
+```example
+Correct: We have a large family. My sister has five children. My great grandmother, however, had nineteen grandchildren before she died.
+```
+
+
+If, however, the numbers refer to two different things, they can be written differently.
+
+Numbers at the beginning of the sentence should also be spelled out with the exception of years:
+
+```example
+Correct: Two-thirds of the class scored in the mid 80s in their final exam.
+```
+
+
+```example
+Correct: 1564 is the year when Shakespeare was born.
+```
+
+
+> **Rule To Remember**
+>
+> Spell out numbers at the beginning of the sentence, with the exception of years.
+
+Numbers that represent years, days of month, pages, chapters, street addresses, route numbers, percentages, temperatures, and telephone numbers should be written as numerals.
+
+```example
+Correct: In all, 78% of voters backed the changes to the constitution while 17% were undecided. Those against the changes had 5% of the votes.
+```
+
+
+```example
+Correct: Classes at NIU begin no earlier than 8:00 a.m.
+```
+
+
+```example
+Correct: Sherlock Holmes lived at 221B Baker Street, London.
+```
+
+
+```example
+Correct: Gas prices are now more than $3.00 a gallon.
+```
+
+
+```example
+Correct: The Battle of Gettysburg ended on July 3, 1863.
+```
+
+
+Numbers should be written as numerals when accompanied by abbreviations such as lb, in, mph, rpm, etc.
+
+```example
+Correct: More fuel efficient cars with at least 30 mpg or better are much easier to sell.
+```
+
+
+However, those same numbers should be expressed in plural when there is no preceding number, or when the numbers are used to express generalized statements.
+
+```example
+Correct: I looked at dozens of websites during my research process.
+```
+
+
+```example
+Correct: Hundreds of people attended the exhibition opening.
+```
+
+
+```example
+Correct: Stonehenge has stood for thousands of years.
+```
+
+
+Do not use the apostrophe to form the plural form of a numeral.
+
+```example
+Correct: The first incandescent light bulb was invented by Thomas Edison in the late 1870s.
+```
+
+
+An apostrophe may precede a numeral expressing a decade, as in
+
+```example
+Correct: The current decline in the housing market is often compared to the one in the '80s.
+```
+
+
+When the word o'clock is used, the word expressing time should be spelled out; otherwise, a.m., p.m. should be used with a numeral.
+
+If neither o'clock or a.m./p.m. are used in the sentence, the time should be spelled out.
+
+```example
+Correct: The meeting is scheduled at four in the afternoon.
+```
+
+
+```example
+Correct: The meeting is at 4:00 p.m.
+```
+
+
+```example
+Correct: We are meeting at two-thirty tomorrow.
+```
+
+
+> **Rule To Remember**
+>
+> - Spell out time when no a.m. or p.m. is used.
+> - Spell out simple fractions.
+
+When the date includes month, day, and year, a comma should be used to set off the year. If only the month is used, no commas are needed.
+
+```example
+Correct: Our first mortgage payment is due October 15, 2007.
+```
+
+
+```example
+Correct: Our first trip to Europe was in October 2006.
+```
+
+
+Simple fractions should be spelled out. A more complex fraction can be represented as a numeral unless it is at the beginning of the sentence.
+
+```example
+Incorrect: 1/3 of our income goes toward the mortgage payment.
+```
+
+
+```example
+Correct: One-third of our income goes toward the mortgage payment.
+```
+
+
+With large numbers consistency and simplicity are very important.
+
+```example
+Incorrect: Depending on the interest rate, your mortgage payment can be as low as five hundred or as high as $1,500.
+```
+
+
+```example
+Correct: Depending on the interest rate, your mortgage payment can be as low as $500 or as high as $1,500.
+```
+
+
+```example
+Correct: Depending on the interest rate, your mortgage payment can be as low as five hundred or as high as fifteen hundred.
+```
+
+> **Rule To Remember**
+>
+> - Hyphenate compound numbers.
+> - Use commas to separate thousands, millions, etc.
+
+Compound numbers should be hyphenated.
+
+```example
+Correct: They had twenty-five tickets available.
+```
+
+
+Commas should separate thousands, millions, etc. And a decimal point should be used with decimal numbers.
+
+```
+$1,200,000
+$1,200.15
+```
+
+---
+
+<!-- TODO: add quiz -->