【正文】
隨堂練習 ( C )1. I ___________ frustrated when I wasn’t sure of the correct answer. A. may be B. used to C. used to be D. use to be ( B ) 2. When I was a child, I used to ___________ chocolate. A. liking B. like C. liked D. likes ( B ) 3. ___________ work in Microsoft? A. Did you used to B. Did you use to C. Do you used to D. Do you use to ( B )4. Where ___