手偶然碰到针尖后，会发生缩手反射。下列叙述中正确的是[ ]

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问题选择题

A．先感到疼痛后缩手

B．先缩手后感到疼痛

C．缩手和疼痛同时发生

D．此反射属于条件发射

答案

答案：B

选择题

---I don't suppose the police know who did it.

---Well, surprisingly they do. A man has been arrested and ____ now.

A．has been questioned

B．is being questioned

C．is questioning

D．has questioned

选择题

----Be careful not to drop the Ming Dynasty vase. ----Yes, we can’t be _____.

A．too careful

B．very careful

C．too careless

D．careless enough