—I since I was 11. Now I am thinking about picking it up again.
—Good for you!
A:wasn't painting
B:haven't painted
C:didn't paint
D:won 't paint
植物细胞中可以将太阳能转换为化学能的结构是( )
某课外小组设计了测定空气中氧气含量的实验,按下图进行实验:
关于亚洲海陆位置的叙述,错误的是( )