问题补充：
---?
---Three.
A. What can you see in the sky?
B. Is there a plane in the sky?
C. How many planes are there?
D. Where is the plane?
答案：
A. What can you see in the sky?
B. Is there a plane in the sky?
(答案→)C. How many planes are there?
D. Where is the plane?
解析：本题主要考查情景交际，根据答语，说明是问句是问多少，故选C。
