题干
You just catch a cold. There is nothing to ___________.
A：worry about
B：worry
C：be worrying
D：be worry
答案(点此获取答案解析）
A
You just catch a cold. There is nothing to ___________.
A：worry about
B：worry
C：be worrying
D：be worry
满足
，且数列
是等比数列，若
，则