切手

切手

Postage stamp.

Here '切手' (stamp) is being identified as an object in a simple noun structure.

これは切手です。

This is a stamp.

In this sentence, '切手' (stamps) is used as the direct object of the verb '集める' (collect).

切手を集めるのが趣味です。

Collecting stamps is my hobby.

Here '切手' (stamp) is modified by a demonstrative 'その' (that) and described with an adjective '珍しい' (rare).

その切手はとても珍しいです。

That stamp is very rare.