if引导的条件状语从句 — 英语词汇题
题目
用 if 引导的条件状语从句补全句子（每空一词，注意主将从现）。1. If it ______ tomorrow, we won't have the picnic. (rain) 2. If you ______ the teacher, she ______ you how to plant trees. (ask; help) 3. If people don't save water, there ______ less fresh water in the future. (be)