A:badly in need of paint
B:bad in need of painting
C:badly in needing of paint
D:badly in need of painting
生活在草丛里的蚂蚱,体色是绿色的混在草丛中,难以发现,形成这种现象的原因是( )
如图是肾蕨和葫芦藓的结构示意图,请据图回答下列问题.
①多肽 ②淀粉 ③纤维素 ④脂肪.