问题详情：
词汇；用括号中所给词的适当形式填空。
1. We should speak to the old _________ (polite).
2. It’s difficult for him to make a (decide) right now.
3. （read）aloud can improve your pronunciation.
classroom (clean) by the students every day.
5. (leaf) turn yellow in autumn.
【回答】
1. tely 2. decision 3. Reading
4. is cleaned 5. Leaves
知识点：构词法
题型：完成句子
