基层协会的理事应以()为主。
A、群众会员
B、干部
C、党员
参考答案:A
若等比数列an满足anan+1=16n,则公比为( )
A.2
B.4
C.8
D.16
There are three ________ students in their school.
A.thousands of
B. thousand of
C. thousands
D. thousand