1 . It was not until Caroline Unger, one of the singers, took his arm and turned him to face the audience ________ the great man realized his symphony was _______ success.（用适当的词填空）

2 . It was at the school gate _____________we gave the foreign visitors a warm welcome. (用适当的词填空)

3 . It was only due to the ongoing support of his wife, parents and friends ____ he eventually found the will to live again. (用适当的词填空)

4 . It was 80 years before Christopher Columbus crossed the Atlantic ________Zheng He had sailed to East Africa. （用适当的词填空）

6 . It was at our college library _____ I borrowed the novel. (用适当的词填空)

7 . It is with your generous help ________ I firmly believe that I will adapt to the college life as soon as possible. （用适当的词填空）

8 . It is at the hotel ________ the coach picks up tourists. (用适当的词填空)

9 . It was this campaign ________ established the paper’s reputation. （用适当的词填空）

10 . Was it________Jack came late for school that Mr. Smith got angry?