情态动词should提出环保建议 — 英语填空题
题目
Tom 想为保护地球做贡献。请根据提示，用情态动词 should（或其否定形式 shouldn't）完成句子，每空一词：
1. We waste water. We ___ save water every day.
2. There are fewer and fewer trees. We ___ plant more trees.
3. It's bad to throw rubbish everywhere. We ___ throw rubbish into the river.（填否定形式）