Famous is an adjective. Adjectives describe nouns (e.g. fountain). Adjectives come before the noun they modify:

That’s the famous fountain.

Adjectives can also stand alone after a verb: This cemetery is peaceful. Note that the adjective always has the same form in singular and plural:

• a cute puppy (one puppy)
• cute puppies (many puppies)

A lot of adjectives end in –ing or –ed. These adjectives derived from verbs are also called the present participle (e.g. fascinating) and the past participle (e.g. relaxed).

• The present participle is formed by adding the ending –ing to the verb in the same way as in the continuous form of the verb: She had an exciting adventure. (excite -> exciting)
• The past participle is formed from the 3rd form of the verb, the –ed ending with regular verbs and irregular verbs to be memorised:

The excited children ran to the park. (excite -> excited)

She read the written instructions carefully. (write -> written)

Adjectives can be used to form nouns, which often describe a particular group of people. These nouns are preceded by the definite article the, and are always plural.

The rich have a lot of money.
The young are the future of our nation.
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