Adjectives... The Keywords to Describe your World.

 Source: Wikipedia and Englisch-hilfen

In Grammar, an adjective is a 'describing' word; the main syntactic role of which is to qualify a noun or noun phrase, giving more information about the object signified.

Adjectives are one of the traditional eight English parts of speech, although linguists today distinguish adjectives from words such as determiners that formerly were considered to be adjectives. In this paragraph, "traditional" is an adjective, and in the preceding paragraph, "main" is.

Usage

A given occurrence of an adjective can generally be classified into one of four kinds of uses:

1. Attributive adjectives are part of the noun phrase headed by the noun they modify; for example, happy is an attributive adjective in "happy people". In some languages, attributive adjectives precede their nouns; in others, they follow their nouns; and in yet others, it depends on the adjective, or on the exact relationship of the adjective to the noun. In English, attributive adjectives usually precede their nouns in simple phrases, but often follow their nouns when the adjective is modified or qualified by a phrase acting as an adverb. For example: "I saw three happy kids", and "I saw three kids happy enough to jump up and down with glee."
2. Predicative adjectives are linked via a copula or other linking mechanism to the noun or pronoun they modify; for example, happy is a predicate adjective in "they are happy" and in "that made me happy." 
3. Absolute adjectives do not belong to a larger construction (aside from a larger adjective phrase), and typically modify either the subject of a sentence or whatever noun or pronoun they are closest to; for example, happy is an absolute adjective in "The boy, happy with his lollipop, did not look where he was going."
4. Nominal adjectives act almost as nouns. One way this can happen is if a noun is elided and an attributive adjective is left behind. In the sentence, "I read two books to them; he preferred the sad book, but she preferred the happy", happy is a nominal adjective, short for "happy one" or "happy book". Another way this can happen is in phrases like "out with the old, in with the new", where "the old" means, "that which is old" or "all that is old", and similarly with "the new". In such cases, the adjective functions either as a mass noun (as in the preceding example) or as a plural count noun, as in "The meek shall inherit the Earth", where "the meek" means "those who are meek" or "all who are meek".

Adjective Order

In many languages, attributive adjectives usually occur in a specific order. In general, the adjective order in English is:

opinion
size
shape
age
color
origin
material

So, in English, adjectives pertaining to size precede adjectives pertaining to age ("little old", not "old little"), which in turn generally precede adjectives pertaining to color ("old white", not "white old"). So, we would say "One (quantity) nice (opinion) little (size) old (age) white (color) brick (material) house."
This order may be more rigid in some languages than others; in some, like Spanish, it may only be a default (unmarked) word order, with other orders being permissible.
Due partially to borrowings from French, English has some adjectives that follow the noun as post-modifiers, called post-positive adjectives, such as time immemorial. Adjectives may even change meaning depending on whether they precede or follow, as in proper: They live in a proper town (a real town, not a village) vs. They live in the town proper (in the town itself, not in the suburbs). All adjectives can follow nouns in certain constructions, such as tell me something new.

Adjectives, ending in -ing and -ed

There are adjectives ending in -ing and -ed. These are participle constructions, used like adjectives. Here are some examples:
A) Here the adjective is put before the noun:
Yesterday I read an amusing story in a magazine.
Doris has a boring job.
We watched the group of excited people.


B) Here the adjective is put after the verb:
I was not at all amused by the discussion.
Children get bored very quickly.
The end of the film was really exciting for me.

 Comparison of adjectives

There are three forms of comparison:

- positive
- comparative
- superlative

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A - Comparison with -er/-est

clean - cleaner - (the) cleanest

We use -er/-est with the following adjectives:

1) Adjectives with one syllable

positive	comparative	superlative
clean	cleaner	cleanest
new	newer	newest
cheap	cheaper	cheapest

2) Adjectives with two syllables and the following endings:

2 - 1) Adjectives with two syllables, ending in -y

positive	comparative	superlative
dirty	dirtier	dirtiest
easy	easier	easiest
happy	happier	happiest
pretty	prettier	prettiest

2 - 2) Adjectives with two syllables, ending in -er

positive	comparative	superlative
clever	cleverer	cleverest

2 - 3) Adjectives with two syllables, ending in -le

positive	comparative	superlative
simple	simpler	simplest

2 - 4) Adjectives with two syllables, ending in -ow

positive	comparative	superlative
narrow	narrower	narrowest

3) Spelling of the adjectives using the endings -er/-est

positive	comparative	superlative	comment
large	larger	largest	leave out the silent -e
big	bigger	biggest	Double the consonant after short vowel
sad	sadder	saddest
dirty	dirtier	dirtiest	Change -y to -i (consonant before -y)
shy	shyer	shyest	Here -y is not changed to -i. (although consonant before -y)

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B - Comparison with more - most

positive	comparative	superlative
difficult	more difficult	(the) most difficult

all adjectives with more than one syllable (except some adjectives with two syllables - see
2 - 1 to 2 - 4)

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C - Irregular adjectives

positive	comparative	superlative	comment
good	better	best
bad	worse	worst
much	more	most	uncountable nouns
many	more	most	countable nouns
little	less	least
little	smaller	smallest

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D - Special adjectives

Some adjectives have two possible forms of comparison (-er/est and more/most).

positive	comparative	superlative
clever	cleverer / more clever	cleverest / most clever
common	commoner / more common	commonest / most common
likely	likelier / more likely	likeliest / most likely
pleasant	pleasanter / more pleasant	pleasantest / most pleasant
polite	politer / more polite	politest / most polite
quiet	quieter / more quiet	quietest / most quiet
simple	simpler / more simple	simplest / most simple
stupid	stupider / more stupid	stupidest / most stupid
subtle	subtler / more subtle	subtlest / most subtle
sure	surer / more sure	surest / most sure

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E - Difference in meaning with adjectives:

positive	comparative	superlative	comment
far	farther	farthest	distance
	further	furthest	distance or time
late	later	latest
	latter	x
	x	last
old	older	oldest	people and things
	elder	eldest	people (family)
near	nearer	nearest	distance
	x	next	order