Explanation

Several words are sometimes used as adverbs or sometimes used as prepositions.

A word is a preposition when it governs a noun or a pronoun, It is an adverb when it does not.

He moved on. “On” is an adverb here

Keep your books on the table. “On” is a preposition here

Explanation

Here the word in is an Adverb because it is given in the end.

Explanation

Several words are sometimes used as adverbs or sometimes used as prepositions.

A word is a preposition when it governs a noun or a pronoun, It is an adverb when it does not.

Do you want to come in? “In” is an adverb here

Is he in his room? “In” is a preposition here