Who _______ we _______ swimming with tomorrow afternoon?[ ]

A. will; go

B. do; go

C. will; going

D. shall; go

空气与呼出气体中，所含气体的比较，正确的是

①氧气：空气＞呼出气体  ②二氧化碳：空气＜呼出气体  ③水蒸气：空气＞呼出气体． [ ]

A．①②

B．②③

C．①③

D．①②③