1.Who is this man?
2.Is this man your best friend?
3.Who is your best friend?
4.This man is your friend, isn't he?
5.Is this man your best friend, or another?
1.Was it a problem for you?
2.What it was for you?
3.It was a problem for you, isn't it?
4.For what person it was a problem?
5.It was a problem for you or for her?
1.How did he swim last year?
2.Who did swim better last year?
3.When did he swim better?
4.He swam better last year, isn't he?
5.He swam better last or this year?