问题补充：
----Mike wants to know if a picnic tomorrow.
---- Yes. But if it , we will visit the museum instead.
A. you have; will rain
B. you will have; will rain
C. you will have; rains
D. will you have; rains
答案：
A. you have; will rain
B. you will have; will rain
(答案→)C. you will have; rains
D. will you have; rains
解析：句意：麦克想知道明天你是否去野炊。是的，但是如果下雨的话，我们将改去参观博物馆。if意为“是否”时，引导宾语从句，句中有tomorrow，用一般将来时态，第二空中if引导条件状语从句意为“假如”，主句用将来时从句用一般现在时表示将来，故选C
