They have gone to Beijing for a meeting. They will be back ________.
A:after a few weeks
B:in a few week's time
C:in a few weeks' time
D:for a few weeks
如图,点A位于点O北偏西____.
试一试,看你有几种填法.
0.27×( )=0.( )×( )=0.54
--Yes, because I often stay up late at night.
蝗虫的幼虫和成虫的主要区别是( )
①态明显不同
②生活习性显著不同
③身体大小不同
④生殖器官成熟状况不同⑤翅的发育状况不同