He is only too ready to help others, seldom, ____, refusing them when they turn to him.A. if never B. if ever C. if not D . if any
The teacher asked the students to do the experiment __________ small groups.
The website is very popular. And it’s amazing that __________ designer of it is just __________ nine-year-old child.
I think_____ impresses me about his painting is the colors he uses.
I don’t really like the author _____ I have to admit his books are very exciting.
---When shall I call, in the morning or afternoon?----_____. I’ll be in all day.