Some adjectives are only used in attributive position. After a verb we use other words. Examples of such adjectives are: elder, eldest, live, old, little, mere and sheer.
His elder son is a pilot.
My eldest brother lives abroad.
My eldest brother is six years older than me. (NOT My eldest brother is six years elder than me.)
Elder cannot be used in the predicative (after a verb) position.
They don’t sell live fish.
That fish is still alive. (NOT That fish is still live.)
Live cannot be used in the predicative position.
When old refers to relationships that have lasted a long time, it is only used in the attributive position.
He is an old friend of mine.
Note that an old friend is not the same as a friend who is old.
They have a nice little house in the city.
Their house is very small. (NOT Their house is very little.)
Little cannot be used in the predicative position.
She is a mere child. (BUT NOT That child is mere.)
That is sheer madness. (BUT NOT That madness is sheer.)
When an adjective goes before a noun, it is said to be in the attributive position.
When an adjective goes after be and other copular verbs, it is said to be in the predicative position. Note that an adjective used in the predicative position is not followed by a noun.