【问】 “They say you're a very good chess player. ”

“Well，I have been playing____many years，but I am hardly an expert. ”

A. since B. during

C. for D. from(TOEFL，1973. 3)

答案为C(for)。但我不明白为什么不能选B(during)。难道during不能与时间段连用吗?

【答】 介词for与介词during之后都跟的是时间段(an hour，two weeks，three years，holidays)。但for是指持续时间的长短，回答how long? (多长时间?)的问题，而during则是指动作所发生的时间，回答when? (什么时候?)的问题。下面的例句能清楚地说明这种区别：

1. The child woke three times during the night. (Snow)

这孩子夜里醒了三次。

2. Only two trains left during the morning. (LDCE)

上午只开走了两班火车。

3. He swims every day during the summer. (LDCE)

夏天他每天去游泳。

4. There's no need to take the cottage for all summer.

没有必要整个夏天都租用那个农舍。

5. He stayed in Beijing for two years.

他在北京住了两年。