1) The city ------is very large. (put pronoun)

The city is very large. Isn’t it?

Here the ‘it’ referring to the city is a pronoun. *The pronoun replaces the noun in the subject.

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2) Few people are free from faults.
Few denotes not many

3) a live dog is better than a dead lion

4) What are you doing here. (put interjection).

Hello! “What are you doing here”?

Interjections are words used to express sudden emotions like shock or surprise.

5) A word is enough for counselling

A word is enough for counselling

4) You are mistaken. (put adverb).

Surely, you are mistaken (or) undoubtedly, you are mistaken.

Here, surely and undoubtedly are adverbs. It emphasizes the meaning of the sentence.