Tom likes to stay at home.Tom doesn't like to go shopping（合并成一句）
问题描述：
Tom likes to stay at home.Tom doesn't like to go shopping（合并成一句）
Tom prefers staying at home _______ ________ shopping.
We will have no water to drink unless we learn to save water.（保持句意基本不变）
We will have no water to drink ________ we_________ learn to save water.
答
Tom prefers staying at home to go shopping
We will have no water to drink if we don't learn to save water