3 . 词性转换
1. habitable adj.适合居住的→ ________________ (反) adj.不适宜居住的
2. frequent adj.频繁的；时常发生的 v．常去，常到→ ________________ adv.频繁地；经常→________________ n．频率;频繁
3. annual adj.每年的；一年的 n．年刊；年鉴→ ________________ adv.每年地
4. smog n．烟雾(烟与雾混合的空气污染物)→ ________________ adj.有烟雾的
5. regular adj.定期的；有规律的→ ________________ adj.(反义词)无规律的；不规则的→ ________________ n．章程;规章制度
6. tolerate vt.忍受；包容；容许→ ________________ adj.宽容的；容忍的→ ________________ n．容忍
7. conservation n．(对环境、文物等)保护；保持→ ________________ vt.保护；节约；保存

4 . In addition to new words like “contactless deliver”, the ________ (frequent) of words like “cheer up” and “want to see you” was significantly higher in 2020 than in 2019. (所给词的适当形式填空）

6 . The high___________ of catching colds caused Tom to make a ___________visit to the doctor，who advised him to take exercise___________.(frequent)（所给词的适当形式填空）

8 . 汉译英
1. ________n.居住地；栖息地→　________ adj. 适合居住的
2. ________vt.维持；遭受；承受住→　________ adj.可持续的；合理利用的
3. ________ v.理解；领悟；懂→　________ n.理解力→________adj.全部的；所有的；详尽的
4. ________ adj. 经常的；规律的→________ adv. 频繁地；经常
5. ________ vt. 限制；限定；束缚→________ n.限制规定；限制法规；约束