题干
——Does he often _________?
——No, he often goes to bed early.
A：go to the movies
B：watch TV
C：exercise
D：stay up late
答案(点此获取答案解析）
D
——Does he often _________?
——No, he often goes to bed early.
A：go to the movies
B：watch TV
C：exercise
D：stay up late
的前n项和为
是一个定值，那么下列各数中也为定值的是（ ）
