问题
选择题
Christina wasn’t saying anything, but the professor smiled at her _______she had done something very clever.
A．as if
B．now that
C．while
D．though
答案
A
题目分析：考查连词;A. as if好像，B. now that既然，C. while虽然，当…时候，D. though虽然，句意：Christina没有说什么，但教授对她微笑，好像她做了聪明的事。选A。
点评：连词要记住各个连词的词义，在做题时要注意上下文的逻辑关系。