21. — Thank you very much for helping me when I was in trouble.
— _____.
A. Don't mention it B. With pleasure C. That's right D. You said it
22. It is acknowledged that ___ shortest distance between persons is ___ sincere smile..
A. A; the B. The; / C. A ; / D. The ; a
23. He hasn’t got any hobbies---_______ you call watching TV a hobby.
A. If B. Unless C. When D. Since
