Thanks to my friends in the Perdue University Writing Program for contributing to this grammar resource. And thanks to my friend, The Grammar Girl, Mignon Fogarty. She has many more grammar tips for you here

Articles

What is an article? Basically, an article is an adjective. Like adjectives, articles modify nouns.

English has three articles: the, a, an. Use the to refer to specific or particular nouns. Use a & an to modify non-specific or non-particular nouns.

the = definite article

a/an = indefinite articles

For example, if I say, “Let’s read the book,” I mean a specific book. If I say, “Let’s read a book,” I mean any book rather than a specific book.

Using a or an depends on the sound that begins the next word.

  • a + singular noun beginning with a consonant: a boy; a car; a bike; a zoo; a dog
  • an + singular noun beginning with a vowel: an elephant; an egg; an apple; an idiot; an orphan
  • a + singular noun beginning with a consonant sound: a user (sounds like ‘yoo-zer,’ i.e. begins with a consonant ‘y’ sound, so ‘a’ is used);a university; a unicycle
  • an + nouns starting with silent “h”: an hour
  • a + nouns starting with a pronounced “h”: a horse

If the noun is modified by an adjective, the choice between a and an depends on the initial sound of the adjective that immediately follows the article:

  • a broken egg
  • an unusual problem
  • a European country (sounds like ‘yer-o-pi-an,’ i.e. begins with consonant ‘y’ sound)

Definite Article: the

Use the before singular and plural nouns when the noun is specific or particular. Using the shows that the noun is definite, that it refers to a particular member of a group. For example:

“The dog that bit me ran away.” Here, we’re talking about a specific dog, the dog that bit me.

“I was happy to see the policeman who saved my cat!” Here, we’re talking about a particular policeman. Even if we don’t know the policeman’s name, it’s still a particular policeman because it is the one who saved the cat.

Use the with things you can’t count.

Or you can omit the entirely.

  • “I love to sail over the water” (some specific body of water) or “I love to sail over water” (any water).
  • “He spilled the milk all over the floor” (some specific milk, perhaps the milk you bought earlier that day) or “He spilled milk all over the floor” (any milk).

Use a or an only with things you can count.

  • “I would like a bottle of water.”
  • “Please give me a new glass of milk.”

Indefinite Articles: a & an

How do you know when to use these articles?

The choice of article is actually based upon the phonetic (sound) quality of the first letter in a word, not on the orthographic (written) representation of the letter.

If the first letter makes a vowel-type sound, you use “an”. If the first letter makes a consonant-type sound, you use “a.” Follow these basic rules when deciding to use “a” or “an”.

“A” goes before words that begin with consonants.

  • a cat                           • a dog                      • a purple onion
  • a buffalo                     • a big apple               • a quick question

“An” goes before words that begin with vowels:

  • an apricot                • an egg                    • an investigation
  • an orbit                   • an uprising

Exceptions

Use “an” before unsounded “h”. Because the “h” has no sound, the sound that follows the article is a vowel.

  • an honorable peace                • an honest error

When “u” sounds like the “y” in “you,” or “o” makes the same sound as “w” in “won,” then you use “a”.

  • a union                     • a united front                        • a unicorn

Adjectives

A countable noun is one that can be expressed in plural form, usually with an “s.” For example, “cat--cats,” “season--seasons,” “student--students.”

An uncountable noun is one that usually cannot be expressed in a plural form. For example, “milk,” “water,” “air,” “money,” “food.” It is not correct to say: “He had many moneys.”

Most of the time, this doesn’t matter with adjectives. For example, you can say, “The cat was gray” or “The air was gray.”

But, the difference between a countable and uncountable noun does matter with certain adjectives, like these:

  • some/any
  • much/many
  • little/few
  • a lot of/lots of
  • a little bit of
  • plenty of
  • enough
  • no

Some/Any:

Both “some” and “any” can modify countable and uncountable nouns.

“There is some water on the floor.”      “There are some men here.”   “Do you have any food?”  “Do you have any apples?”

Much/Many:

“Much” modifies only uncountable nouns.

  • “They have so much money in the bank.”
  • “The horse drinks so much water.”

“Many” modifies only countable nouns.

  • “Many Americans travel to Argentina.”
  • “I collected many sources for my report.”

Little/Few:

“Little” modifies only uncountable nouns.

  • "He had little food in the house.”   
  • “When I was in college, there was little money to spare.”

“Few” modifies only countable nouns.

  • “There are a few doctors in town.”  
  • “He had few reasons for his opinion.”

A lot of/lots of:

“A lot of” and “lots of” are informal substitutes for much and many. They are used with uncountable nouns when they mean “much” and with countable nouns when they mean “many.”

  • “They have lots of (much) money in the bank.”
  • “A lot of (many) Americans travel to Europe.”
  • “We got lots of (many) mosquitoes last summer.”
  • “We got lots of (much) rain last summer.”

A little bit of:

“A little bit of” is informal and always precedes an uncountable noun.

  • “There is a little bit of pepper in the soup.”
  • “There is a little bit of snow on the ground.”

Plenty of:

“Plenty of” modifies both countable and uncountable nouns.

  • “They have plenty of money in the bank.”
  • “There are plenty of millionaires in Switzerland.”

Enough:

Enough modifies both countable and uncountable nouns.

  • “There is enough money to buy a car.”
  • “I have enough books to read.”

No:

No modifies both countable and uncountable nouns.

  • “There is no time to finish now.”
  • “There are no squirrels in the park.”

Prepositions for Time, Place, and Introducing Objects

Use on with days:

  • I will see you on Monday.
  • The week begins on Sunday.

Use at  with noon, night, midnight, and the time of day:

  • My plane leaves at noon.
  • The movie starts at 6 p.m.

Use in with other parts of the day, with months, with years, with seasons:

  • He likes to read in the afternoon.
  • The days are long in August.
  • The book was published in 1999.
  • The flowers will bloom in spring.

Extended time

To express extended time, English uses these prepositions: since, for, by, to, from, until, during, within

  • She has been gone since yesterday. (She left yesterday and has not returned.)
  • I’m going to Paris for two weeks. (I will spend two weeks there.)
  • The movie showed from August to October. (Beginning in August and ending in October.)
  • The decorations were up from spring until fall. (Beginning in spring and ending in fall.)
  • I watch TV during the evening. (For some period of time in the evening.)
  • We must finish the project within a year. (No longer than a year.)

Place

To express place, English uses these prepositions to talk about the point itself: in, to express something contained: inside, to talk about the surface: on, to talk about a general vicinity, at.

  • There is a wasp in the room.
  • Put the present inside the box.
  • I left your keys on the table.
  • She was waiting at the corner.

Higher than a point

To express notions of an object being higher than a point, English uses these prepositions: over, above.

  • He threw the ball over the roof.
  • Hang that picture above the couch.

Lower than a point

To express notions of an object being lower than a point, English uses these prepositions: under, underneath, beneath, below.

  • The rabbit burrowed under the ground.
  • The child hid underneath the blanket.
  • We relaxed in the shade beneath the branches.
  • The valley is below sea-level.

Close to a point

To express notions of an object being close to a point, English uses these prepositions: near, by, next to, between, among, opposite.

  • She lives near the school.
  • There is an ice cream shop by the store.
  • An oak tree grows next to my house
  • The house is between Elm Street and Maple Street.
  • I found my pen lying among the books.
  • The bathroom is opposite that room.

Pronouns

There are four cases of pronouns.

  • Subjective: used as subject.
  • Objective:  used as objects of verbs or prepositions.
  • Possessive: express ownership.
  • Reflexive: use to refer to self                  

Subjective                                      Objective                                    Possessive                         Reflexive

I                                                            me                                                   my (mine)                                         myself

you                                                      you                                                  your (yours)                                       yourself

he, she, it                                            him, her, it                                    his, her (hers), it (its)                      himself, herself, itself

we                                                        us                                                     our (ours)                                           ourselves

they                                                     them                                               their (theirs)                                      themselves

who                                                     whom                                             whose

 

How to know when to use I or me

When there are two pronouns, or a noun and a pronoun, drop the other noun for a moment. Then you can see which case you want.

Not: Bob and me travel every month.
(Would you say, “me travel”?)

Not: He gave the flowers to Jane and I.
(Would you say, “he gave the flowers to I”?)

Not: Us men like the coach.
(Would you say, “us like the coach”?)

When describing a comparison use than or as:

He is taller than I (am tall).

This helps you as much as (it helps) me.

She is as noisy as I (am).

Comparisons are really shorthand sentences which usually omit words, such as those in the parentheses in the sentences above. If you complete the comparison in your head, you can choose the correct case for the pronoun.

Not: He is taller than me.
(Would you say, “than me am tall”?)

Sentences

Parallel Structure

Parallel structure means using the same pattern of words to show that two or more ideas have the same level of importance.

You join parallel structures with and or or

Mary likes hiking, swimming, and bicycling.

Mary likes to hike, to swim, and to ride a bicycle.

Mary likes to hike, swim, and ride a bicycle. 

Do not mix verb forms like these:

Not: Mary likes hiking, swimming, and to ride a bicycle.

Instead: Mary likes hiking, swimming, and riding a bicycle.

Not: The production manager wrote his report quickly, accurately, and in a detailed manner.

Instead: The production manager wrote his report quickly, accurately, and thoroughly.

Not: The teacher said that he was a poor student because he waited until the last minute to study for the exam, completed his lab problems in a careless manner, and his motivation was low.

Instead: The teacher said that he was a poor student because he waited until the last minute to study for the exam, completed his lab problems in a careless manner, and lacked motivation.

Be sure to keep all the elements in a list in the same form.

Not: The dictionary can be used for these purposes: to find word meanings, pronunciations, correct spellings, and looking up irregular verbs.

Instead: The dictionary can be used for these purposes: to find word meanings, pronunciations, correct spellings, and irregular verbs.

Subject/verb agreement

When the subject of a sentence has two or more nouns or pronouns connected by and, use a plural verb.

She and her friends are at the fair.

When two or more singular nouns or pronouns are connected by or or nor, use a singular verb.

The book or the pen is in the drawer.

When a compound subject has both a singular and a plural noun or pronoun joined by or or nor, the verb should agree with the part of the subject that is nearer the verb.

The boy or his friends run every day.

Neither his friends nor the boy runs every day.

Use doesn’t only with a singular subject.

Use don’t only with a plural subject.

He doesn’t like it. They don’t like it.

The words each, each one, either, neither, everyone, everybody, anybody, anyone, nobody, somebody, someone, and no one are singular, so use a singular verb.

Each of these hot dogs is juicy.

Everybody knows Mr. Jones.

Either answer A or B is correct.

Expressions such as with, together with, including, accompanied by, in addition to, or as well do not change the number of the subject. If the subject is singular, the verb is too.

The President, accompanied by his wife, is traveling to India.

All of the books, including yours, are in that box.

Verbs

Simple Present: They walk
Present Perfect: They have walked
Future: They will walk
Simple Past: They walked
Past Perfect: They had walked
Future Perfect: They will have walked

Examples:

Betty teaches Spanish at the high school. Present (Betty teaches now.)

Betty has taught for ten years. Present Perfect (Betty is still teaching.)

Betty will teach for three more years. Future

Betty taught for ten years. Simple Past (Betty is no longer teaching.)

Betty taught my Spanish class last year. Past  

Betty had taught in another state. Past Perfect (She taught somewhere else before she came to this school.)

By next year, Betty will have taught for twenty-five years. (future perfect)

In English, regular verbs consist of three main parts: the root form (present), the (simple) past, and the past participle. Regular verbs have an -ed ending added to the root verb for both the simple past and past participle. 

Irregular verbs do not follow this pattern, and instead often use a different word. Here are a few examples:

Irregular Verbs

                         Present                                  Past                                              Past Participle

                         be                                           was, were                                     been

                         begin                                     began                                          begun

                         break                                     broke                                           broken

                         catch                                     caught                                         caught

                         choose                                   chose                                            chosen

                         do                                           did                                                done

                         drink                                     drank                                           drunk

                         drive                                      drove                                            driven

                         eat                                          ate                                                eaten

                         fall                                         fell                                                fallen

                         fly                                           flew                                              flown

                         forget                                    forgot                                          forgotten

                         get                                          got                                                gotten

                         give                                        gave                                             given

                         go                                           went                                             gone

                         hide                                       hid                                                hidden

                         hold                                       held                                              held

                         keep                                       kept                                              kept

                         know                                     knew                                            known

                         lay                                          laid                                              laid

                         leave                                      left                                                left

                         meet                                      met                                               met

                         pay                                         paid                                             paid

                         read                                       read                                              read (spelled the same, spoken differently!)

                         ride                                        rode                                              ridden

                         say                                          said                                              said

                         see                                          saw                                               seen

                         sing                                        sang                                             sung

                         take                                       took                                             taken

                         teach                                     taught                                         taught

                         tear                                        tore                                               torn

                         throw                                     threw                                            thrown

                         wear                                       wore                                             worn

                         write                                      wrote                                            written

 

The Apostrophe

You can use the apostrophe three ways:

  1. to form possessives of nouns
  2. to show the omission of letters
  3. to indicate certain plurals of lowercase letters

Possessives of Nouns

To see if you need to make a possessive, turn the phrase around and make it an “of the...” phrase. For example:

the boy’s hat = the hat of the boy
three days’ journey = journey of three days

If the noun after “of” is a building, an object, or a piece of furniture, you don’t use an apostrophe!

room of the hotel = hotel room
door of the car = car door
leg of the table = table leg

Once you’ve determined whether you need to make a possessive, follow these rules to create one.

  • add ‘s to the singular form of the word (even if it ends in -s):

the owner’s car                          James’s hat (James’ hat is also acceptable.)

  • add ‘s to the plural forms that do not end in -s:

the children’s game                                  the geese’s honking

  • add to the end of plural nouns that end in -s:

two cats’ toys           three friends’ letters                 the countries’ laws

  • add ‘s to the end of compound words:

my brother-in-law’s money

  • add ‘s to the last noun to show joint possession of an object:

Todd and Anne’s apartment 

Showing omission of letters

A contraction is a word in which one or more letters, or numbers, are omitted. The apostrophe shows this omission. Contractions are common in informal writing. To use an apostrophe to create a contraction, place an apostrophe where the omitted letter(s) or numbers would go. Here are some examples:

dont = do not
Im = I am
hell = he will
whos = who is
shouldnt = should not
didnt = did not
couldve= could have  
60 = 1960

Don’t use apostrophes for personal pronouns, the relative pronoun who, or for noun plurals.

His, her, its, my, yours, ours are all possessive pronouns. These words already show possession, so they don’t need an apostrophe. However, indefinite pronouns, such as one, anyone, other, no one, and anybody, can be made possessive. Here are some examples:

wrong: his’ book
correct: his book
correct: one’s book
correct: anybody’s book

wrong: Who’s dog is this?
correct: Whose dog is this?

wrong: The group made it’s decision.
correct: The group made its decision.

The two words its and it’s are not the same thing. It’s is a contraction for “it is” and its is a possessive pronoun meaning “belonging to it.”

Were you asking us to help?                    We’re glad to help.

Your shoes are untied.                               You’re walking around with your shoes untied.

Showing plural of lower case letters

There are five a’s on this page.

Quotation Marks

Use direct quotations to include another person’s exact words into your own writing.

Capitalize the first letter of a direct quote when the quoted material is a complete sentence.

Mr. Johnson, who was working in his field that morning, said, “The alien spaceship appeared right before my own two eyes.”

Do not use a capital letter when the quoted material is a fragment or only a piece of the original material’s complete sentence.

Although Mr. Johnson has seen odd happenings on the farm, he stated that the spaceship “certainly takes the cake” when it comes to unexplainable activity.

If a direct quotation is interrupted mid-sentence, do not capitalize the second part of the quotation.

“I didn’t see an actual alien being,” Mr. Johnson said, “but I sure wish I had.”

In all these examples, the period or comma punctuation always comes before the final quotation mark. This punctuation rule may change, depending on which reference book you use.

Indirect Quotations

Indirect quotations are not exact wordings but rather re-phrasings or summaries of another person’s words. In this case, it is not necessary to use quotation marks. 

Mr. Johnson, a local farmer, reported last night that he saw an alien spaceship on his own property.

Comma

Use commas to separate independent clauses when they are joined by any of these seven coordinating conjunctions: and, but, for, or, nor, so, yet.

The game was over, but the crowd refused to leave.

The student explained her question, yet the instructor still didn’t seem to understand.

Yesterday was her brother’s birthday, so she took him out to dinner.

Use a comma following these words: after, although, as, because, if, since, when, while.

While I was eating, the cat scratched at the door.

Because her alarm clock was broken, she was late for class.

If you are ill, you ought to see a doctor.

When the snow stops falling, we’ll shovel the driveway.

Having finished the test, he left the room.

To get a seat, you’d better come early.

That Tuesday, which happens to be my birthday, is the only day I am available to meet.

This restaurant has an exciting atmosphere. The food, on the other hand, is rather bland.

My niece, wearing a yellow dress, is playing in the living room.

Apples, which are my favorite fruit, are the main ingredient in this recipe.

Tom, the captain of the team, was injured in the game.

Use commas to separate three or more words, phrases, or clauses written in a series.

The US Constitution establishes the legislative, executive, and judicial branches of government.

The candidate promised to lower taxes, protect the environment, reduce crime, and end unemployment.

Use a comma near the end of a sentence to separate contrasted elements, or to show a distinct pause.

He was merely ignorant, not stupid.

You’re one of the senator’s close friends, aren’t you?

The speaker seemed innocent, even gullible.

Use a comma to shift between the main sentence and a quotation.

Sarah said without emotion, “I’ll see you tomorrow.”