[解析]
13.B 14.C
W:Hi,Joe.What are you going to do this afternoon?
M:I'd like to go swimming.You know,it's my favorite sport.
W:How often do you go swimming?
M:Twice a week.On Friday afternoons and Sunday mornings.
W:Whom do you usually go with,your cousin or your friends?
M:Neither.I usually go with my brother,David.He often teaches me some swimming skills.
W:That must be great fun.
M:Sure!Swimming is really interesting.