Na+从细胞内出来
A．单纯扩散B．易化扩散C．主动转运D．入胞作用E．继发性主动转运
参考答案：C
Do you skate______?
A. a lot quite B. a quite lot C. quite a lot
—How many _____ have you got?
—I've got many. [ ]
A. photoes
B. photo
C. photos
D. a photo
