当细菌外毒素再次侵入人体后，主要是体液免疫发挥作用，其“反应阶段”和“效应阶段”的免

选择方框中的句子完成对话，其中有两项多余。（2.5分）
A: Hi , Tony .___小题1:___ .
B: Yes , of course .
A: ___小题2:___ .
B: Yes , and I swim very well .
A: That’s good .  ___小题3:___.
B: This weekend ? I’m sorry I have to visit my grandparents with my parents then .
A: It’s a pity . __小题4:__ .
B: By the way , are you free next Saturday ?
A: Oh , yes .
B: ___小题5:____
A: Yes , I’d love to .When will it start ?
B: At seven in the evening .
A; I think I’ll be there on time .

Maybe another time . Who taught you to swim . Can I ask you a question ? Do you like swimming ? Can you go swimming with me this weekend ? How about you ? And would you like to come to my birthday party ?