Question

— Do you often go swimming_____ Sunday mornings?
— Yes. Why not _____with me this Sunday?

1. A.
   on, go
2. B.
   in; to go
3. C.
   on; going
4. D.
   in going

Answer 1

A
介词on与Why not的用法。在某一天，或某天某段时间用介词on，Why not do sh.?指“为什么不做某事”，do前是省略to的不定式。故选择A。