精选优质文档-倾情为你奉上一、单项选择。（15分）（ ）1. I_ frustrated when I wasnt sure of the correct answer. A. may be B. used to C. used to be D. use to be（ ）2. When I was a child, I used to _ chocolate. A. liking B. like C. liked D. likes（ ） 3. _ work in Microsoft? A. Did you used to B. Did you use to C. Do you used to D. Do you use to（ ） 4. Where _
