We buy tickets __________ the movie.[ ]
A. to
B. at
C. for
答案：C
一下哪种工具体现“80/20法则”（）.
A、直方图法
B、管制图法
C、柏拉图法
D、检查法
It rained _______ last Sunday, so they didn't go out. [ ]
A. that day
B. a day
C. the day
D. all day
