The differences bewteen "Mere" and "Merely".?

Question

What are the difference between these two sentences:1) He's a mere boy.2) He's merely a boy

Answer 1

The meaning is the same. Both are saying "He is just a boy." However, "mere" is an adjective. It can only be used to describe nouns, such as boy. Merely is an adverb, so it can be used to describe the verb "is" in the second sentence.