一般生物学实验室用水有以下()
A.自来水
B.三类水
C.二类水
D.矿泉水
参考答案:A, B, C
—Here is _________MP5 for you.
—Thank you. It looks like ________‘U’. I like it very much. [ ]
A. a; an
B. an; an
C. an; a
D. a; a
农田生物组成中主要包括什么?