A:Yes, I did
B:No, I didn't
C:Yes, I have
D:Why? Sound strange
8的7倍是56
下列有关显微镜使用的叙述,正确的是( )
如图为叶芽纵剖图。
①是____,使茎不断长长;
②是____,将发育成____;
③是____,将发育成____;
④是____,将来发育成____;
⑤是____,将来发育成____.