分类：教育/科学-外语学习-英语考试
问题：单选49.________theyheardtheshoutfo 
49. ________ they heard the shout for help，they rush out.A. Immediately  B. The moment  C. The while  D. All the above为什么选择D 呢？我没见过C 这种说法,AB 都见过。
回答：就是说，前面三个答案都可以，C.The while/moment=as soon as ,while是名词，类似词语：after a while/moment