---What are you going to do on the weekend, Roy?

---I have no plan yet．I ________ either go on a field trip or go fishing．

1. A.
   may
2. B.
   should
3. C.
   have to
4. D.
   must

?What are you going to do on the weekend, Roy?

?I have no plan yet. I ________ either go on a field trip or go fishing.

A. may

B. should

C. have to

D. must