12th Grade Grammar


Rule 1

Use Commas between the main clauses in a compound sentence.  Place the comma before the coordinating conjunction (and, but, or, nor, yet or for) that joins the two clauses.

 The election is only two months away, and the candidates still have a lot of work ahead of them.


You can omit the comma between very short clauses that are connected by a coordinating conjunction as long as the meaning is clear.

John opened the refrigerator and he took out the milk.  (clear) 

John opened the refrigerator and the milk spilled onto the floor.  (a little confusing)


Rule 2

Use a comma to separate three or more words, phrases, or clauses in a series when they are not connected by conjunction.

The lights blinked, flickered, and went out.

I checked the windows, Susan opened the curtains, and Dad turned on the lights.


Do not use a comma to separate nouns in pairs: 

Salt and pepper

Bread and butter


Rule 3

Place a comma between two coordinate adjectives that precede a noun. 

The tall, thin, red-haired player on the other team was really good.

 Exception: If the adjectives sound unnatural with their order reversed or with 'and' between them, do not use a comma. (Generally, these have to do with size and shape)

Mindy painted a big round face on the mural.


Rule 4

Use a comma to set off a non-essential adjective clause, but do not use a comma to set off a clause that is essential.

Boston, which is in the eastern part of the state, is the capital of Massachusetts.

Tourists who are not fond of the cold weather should avoid vacationing in Alaska.

 Tourists, who are not fond of the cold weather, should avoid vacationing in Alaska.


Rule 5

Use a comma after an introductory phrase only if the sentence would be misread without one.h


Rule 6

Use a comma to set off all introductory adverb clauses and to set off internal adverb clauses that interrupt the flow of the sentence.

Since the concert had already started, we had to wait in the lobby.

David, after he had been accepted into the program, threw his hat into the air.

Rule 7          

Use a comma to set off a title when they follow a person’s name.

Use a comma after the various parts of an address, geographical term, or a date.


A comma is not used when only the month and the day or the        

            month and the year are given.

Use a comma to set off parts of a reference that direct the reader to the exact source.


Rule 8

Use a comma to set off words used in direct address.

Thanks for your help, Mr. Jones.

Hey, man, that’s a cool car.

I saw you at the game yesterday, didn’t I?




Rule 1

Use a colon to introduce a list, especially after a statement that uses such words as these, the following, or as follows.

Do not use a colon if a list comes immediately after a verb.


Rule 2

Use a colon to introduce material that illustrates, restates, or explains preceding material.


Rule 3

Use a colon to introduce a long or formal quotation.



Rule 1

Use a semicolon to separate main clauses that are NOT joined by a coordinating conjunction (and, but, or, nor, yet and for)

A prehensile tail, one that can grasp or wrap around things, has proven to be a valuable aid to survival for many species; the North American opossum and the South American spider monkey are two animals that have this type of tail.


Rule 2

Use a semicolon to separate main clauses joined by a conative adverb such as however, therefore, nevertheless, moreover, furthermore and consequently. 

Which state has the most interesting and unusual place names would be a lively debate; however, Maine, with names such as Passamaquoddy, would win easily. 


Rule 3

Use a semicolon to separate items on a list when these items contain commas.

Three important twentieth-century poets who held jobs outside literature are William Carlos Williams, a doctor; Wallace Stevens, an insurance company executive; and TS Eliot, a banker.




Rule 1

Generally, you do not use a hyphen to join a prefix to a word, but you do use a hyphen after any prefix joined to a proper noun.  Also, use a hyphen after the prefixes
all, ex and self.

pro-American                 ex-governor          all-knowing          self-awareness


Rule 2

Use a hyphen in a compound adjective that precedes a noun.  When compound adjectives beginning with well, ill, or little are modified by an adverb, they are usually not hyphenated.  An expression made up of an adverb ending in
ly and an adjective is not hyphenated.

A dark-colored hat                                     The hat was dark colored.

A well-known musician                              A well known musician

A poorly written play                                 A tightly packed container


Rule 3

Hyphenate any spelled-out cardinal or ordinal number up to ninety-nine or ninety-ninth.  Hyphenate a fraction used as an adjective (but not one used as a noun).

A two-thirds vote                                               two thirds of the vote


Rule 4

Hyphenate two numbers to indicate a span.  When you use the word
from before a span, use to rather than a hyphen.  When you use between, use and.

Pages 568-643                                   1914-1918           

from 1914 to 1918                                    between 12:00 and 1:45