A:18%和82%
B:36%和64%
C:53%和47%
D:76%和24%
血管上皮细胞是扁平的,小肠黏膜上皮细胞是柱状的,肾小管上皮细胞呈正方形,呼吸道上皮细胞表面有能摆动的纤毛。它们的形态结构各不相同的原因是
He thinks watching movies ________.
下列关于南北方人民生活的叙述,不正确的是( )
In the future, working hours will be short. ________ people will have a long holiday.