Adjectives
Adjectives are descriptive words. They can make sentences more interesting by adding color and detail. They can make sentences more exact by qualifying things and actions.
Adjectives always modify nouns. .

Comparative adjectives describe by comparing with something else. Example comparative adjectives include "warmer," "more quickly," and "less difficult."
Superlative adjectives describe by comparing with two or more other things. Superlative adjectives state which thing possesses the most or least of some characteristic. Example superlative adjectives are "warmest," "most quickly," and "least difficult."
Comparative Adjectives
The comparative forms of adjectives compare whatever is described with one other thing. Comparatives are formed by adding the suffix "er" or the words "more" or "less."
Use the suffix "er" when the adjective has one syllable: "quicker," "darker," "louder."
Precede the adjective by "more" or "less" when it has two or more syllables: "more lucky," "more handsome," "less harmonious."
Mixing the two forms is redundant (and incorrect). Use "quicker" instead of "more quicker," for example.
Some comparative adjectives have irregular forms:

worse
inner

Good vs. Well

Many writers are unsure of the distinction between "good" and "well."
"Good" is an adjective, so it normally modifies a noun. "Well" is an adverb, so it normally modifies a verb or an adjective.

My car is running good.

-- "Running" is a verb.

My car is running well.
The new product has sold good in the first quarter.

-- "Sold" is a verb.

The new product has sold well in the first quarter.
The new product has had good sales in the first quarter.

-- "Sales" is a noun.

These guidelines also apply to the adjective "bad" and the adverb "badly."

We did bad in the product-evaluation tests.

-- "Did" is a verb.

We did badly in the product-evaluation tests.


Superlative Adjectives
The superlative forms of adjectives compare whatever is described with at least two other things. Superlative adjectives state which thing in a collection of things possesses the least or most of some characteristic.
Form superlatives by adding the suffix "est" or the words "most" or "least."
Use the suffix "est" when the adjective has one syllable: "quickest," "darkest," "loudest."
Precede the adjective by "most" or "least" when it has two or more syllables: "most lucky," "most handsome," "least harmonious."
Mixing the two forms is redundant (and incorrect). Use "quickest" instead of "most quickest," for example.
Some superlative adjectives have irregular forms:

worst
innermost


Adverbs
Adverbs modify verbs, adjectives, or other adverbs.
Related topics:

Comparative adverbs form part of a comparison with one other thing:

more quickly
less loudly

Superlative adverbs form part of a comparison with two or more other things:

most quickly
least loudly

Split infinitives: Adverbs inserted between "to" and an infinitive verb .



Comparative Adverbs
Use "more" or "less" when the modifier is an adverb: "more quickly," "more darkly," "less loudly."



Superlative Adverbs
Use "most" or "least" when the modifier is an adverb: "most quickly," "most darkly," "least loudly."



Articles
Articles are simple adjectives .
Articles always precede nouns, and identify which noun is referred to.
"A" or "an" are indefinite articles. They refer to any noun :

a house
an apple
a possibility

"The" is a definite article. It refers to one specific noun :

the house
the apple
the possibility

"A" precedes nouns that begin with a consonant sound. "An" precedes nouns that begin with a vowel sound. Note that the first letter of a noun need not be a vowel or consonant for these rules to apply:

a box
a unit
a university
a union
an item
an hour
an heir
an honor


Conjunctions
A conjunction is a joining word that links related words, phrases, and clauses.
Common conjunctions:
and after although as because
before but how or while
if nor once so what
since that though unless






till until
when where whether
why

Do not use "and who," "and which," or "and that" in a sentence unless there is a preceding "who," "which," or "that":

The man I met yesterday and who gave me his theater tickets called this morning.
The man who I met yesterday and who gave me his theater tickets called this morning.

Don't follow "come," "go," or "try" with "and." Use the preposition "to" instead:

I'll try and call you next week.
I'll try to call you next week.

Always use "or" after "either":

Either Elaine or Carol will meet you at the airport.

Always use "nor" after "neither":

Neither Elaine nor Carol are ready, so I will pick you up at the airport.

Generally, use "or" after "not." If the items are closely related, substitute "nor" for "or":

This weather is not fit for skating or swimming.
This weather is not fit for man nor beast.
The tornado had not damaged the house or the car.
He could not rely on friend nor relative.


Interjections
Interjections express strong emotions or exclamations:

oh
whew
damn


Nouns
Nouns represent objects, such as people, places, and things. Nouns can also represent ideas, such as hunger, emotions, or laws. Nouns for classes of people, places and things are called common nouns. Nouns that are the specific names of people, places, and things are proper nouns.
Nouns have the quality of number. A noun representing one object (or less than one, in the case of a part) is singular, while a noun representing more than one is plural.
For example, "the tree" refers to a single tree, so "tree" is singular. "The top of the tree" refers to part of a single tree, so "top of the tree" is singular. "The trees" refers to two or more trees, so "trees" is plural.
Nouns also have the quality of ownership. Nouns having this quality are called possessives. For example, the noun "John" is possessive in the sentence, "We wrapped John's shirt."
Plural Nouns
Plural nouns refer to more than one thing.
A noun is plural even if it is only fractionally greater than one:

one-and-a-half pies

The plural of most nouns is formed by adding the suffix "s." Nouns ending in "s," "z," "x," "ch," or "sh" are made plural by adding the suffix "es":

dog dogs
horse horses
thought thoughts
pickle pickles
waltz waltzes
match matches

Make nouns ending in "y" plural by changing the "y" to "ies," unless the "y" was preceded by a vowel, in which case use just the suffix "s":

duty duties
frailty frailties
key keys
quality qualities
play plays

Nouns ending in "o" are often made plural by adding the suffix "es" (there are exceptions, though -- check the dictionary to be sure):

echo echoes
tomato tomatoes
potato potatoes
zero zeroes or zeros
radio radios

Certain nouns are made plural by adding the suffix "en":

ox oxen
brother bretheren
child children

Some nouns are made plural by changing their vowels:

foot feet
goose geese
louse lice
man men
tooth teeth
woman women

The names of hunted animals have the same forms in the singular and plural:

quail
deer
moose
fish
trout
salmon

Nouns of foreign origin have various exceptional plural forms:

antenna antennae
bacterium bacteria
cactus cacti
cello celli
concerto concerti
criterion criteria
curriculum curricula
datum data
focus foci
formula formulae
larva larvae
medium media
memorandum memoranda
phenomenon phenomena
referendum referenda
syllabus syllabi
vertebra vertebrae
virtuoso virtuosi

To make compound nouns plural, make the most significant part plural using the rules listed above (the most significant part is the part described by the rest of the compound):

arm-chairs
foot-stools
attorneys-general
major-generals
brothers-in-law
hangers-on
maids-of-honor


Possessive Nouns
Possessive nouns own or possess. What they possess can be other nouns ("the car's windshield") or qualities ("the mind's eye," "a moment's notice").
The quality of possession is usually assigned to a noun using the apostrophe.
For singular nouns, form the possessive by adding the suffix "'s." This applies whether the singular noun ends in "s" or not:

Jerry's truck
at year's end
Gus's clothing
the business's concerns
the cat's pyjamas

There are some exceptions to this rule:

Achilles' heel
Jesus' word
goodness' sake

The suffix "'s" can be used even if the noun is an inanimate object.

the car's radiator
the house's roof
my computer's keyboard

Some people prefer to denote possession of inanimate objects using "of":

the radiator of the car
the roof of the house
the keyboard of my computer

For plural nouns, form the possessive by adding a single apostrophe as a suffix:

the girls' picnic
secretaries' day
the boys' coats
the people's choice
the men's room

When two or more nouns jointly possess something, apply the possessive form to the last noun only:

John and Mary's house
Barnes and Noble's products
Thomas and Son's Hardware

When two or more nouns individually possess something similar, apply the possessive form to all nouns:

John's and Mary's birth certificates

When a compound noun possesses, place the "'s" at the end:

my mother-in-law's house
the attorney-general's office

Use "of" to denote possession when the name of the possessor is long or awkward.
Awkward:

the First National Bank of New York's assets
Joe's brother's doctor's cousin
the maids-of-honor's dresses
my brothers-in-law's homes

Better:

the assets of the First National Bank of New York
the cousin of the doctor of Joe's brother
the dresses of the maids-of-honor
the homes of my brothers-in-law




Proper Nouns
Proper nouns are the names of specific people, places, and things. Proper nouns are normally capitalized:

John Smith
The United States of America
the Empire State Building
Florida
Hayes Modem 56000