I used to go swimming when I lived in the countryside. (The verb "used to" is followed by the base form of the verb, not the -ing form)

Most of my students like English. (The subject "most" is followed by the singular verb "likes", but it should be followed by the plural verb "like")

What is the name of the man who is talking to the headmaster? (The relative pronoun "who" is used to refer to people, not "which".)

We wish there weren't any natural disasters in the world. (The verb "wish" is followed by the past simple tense to indicate a present unreal situation, not the present simple tense.)