A:being robbed
B:having been robbed
C:to have been robbed
D:robbed
图为研究生长素(IAA)产生部位及运输方向的实验,初始时,琼脂块①~⑥不含IAA,下列对实验结果的表述中正确的是( )
Today is really a day. I lost all my money. ( )
史前社会人类面临的环境问题有( )
①洪水 ②猛兽 ③风暴 ④废气