We’ll have a picnic if it ______ tomorrow.

A. rains B. will rain C. doesn’t rain D. won’t rain

If it ________ rain tomorrow, we'll have a picnic. But I don't know if it ________ tomorrow.

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I don’t know if it ______ tomorrow. If it ______, we’ll have a picnic.

A. rains; rains    B. will rain; will rain  C. rain, doesn’t rain  D. will rain; doesn’t rain