21. You are saying that everyone should be equal, and this is ______ I disagree.
A. why B. where C. what D. how
22. The road is covered with snow. I can’t understand ______ they insist on going by motorbike.
A. why B. whether C. when D. how
23. —What do you think of the building built to the shape of nature?
—______.
A. Yes, I like its shape B. What I like is the colour
C. It’s really like a bird net D. I really think it is wonderful