Mrs. White, when shall we go for a picnic?---If it , we for a picnic in the park tomo

--- Mrs. White, when shall we go for a picnic?
---If it , we for a picnic in the park tomorrow.
A. rains；will go
B. will rain；go
C. doesn’t rain；will go
D. doesn’t rain；go

A. rains；will goB. will rain；go(答案→)C. doesn’t rain；will goD. doesn’t rain；go解析：句意：--怀特夫人，我们什么时候去野餐？--如果天气不下雨，我们明天将要去公园去野餐。分析答语中运用条件状语从句，体现主将从句的原则。从句中rain为动词，同时主语为单数形式。因此否定形式借助于助动词does.故选 C

我明天再问问老师，叫他解释下这个问题