三、根据汉语意思完成短文。
Max and David are good friends. They share many 21. (相似之处). For example, they are both 22. (外向的) and 23. (勤奋的). They also have the same 24. (业余爱好). Both of them like playing sport very much. Though they have a deep 25. (友谊), they are honest enough to share their true 26. (看法) when they hold different ideas about the same thing. For them, good friends are like 27. (镜子), showing them both their shining points and shortcomings.
Unlike Max and David, Sally and Grace have many 28. (差异). Grace is more direct and has a sense of 29. (幽默) while Sally is really quiet and 30. (害羞的). But they are still good friends. So whether people are the same or different, they can all become friends.

21. similarities
22. outgoing
23. hard-working
24. hobby
25. friendship
26. opinions
27. mirrors
28. differences
29. humor
30. shy

本题考查人教版八年级上册Unit3的核心词汇运用，需结合空格前后的修饰成分判断词性和名词的单复数变化：
1. 第21空：many后要接可数名词复数，“相似之处”的英文单词是similarity，复数形式为similarities；
2. 第22空：此处作表语，“外向的”对应形容词outgoing；
3. 第23空：和outgoing并列作表语，“勤奋的”对应形容词hard-working；
4. 第24空：the same后接名词，此处指代两人共同的爱好，“业余爱好”用单数名词hobby即可；
5. 第25空：不定冠词a后接单数名词，“友谊”对应名词friendship；
6. 第26空：形容词性物主代词their后接可数名词复数，“看法”的英文是opinion，复数形式为opinions；
7. 第27空：主语friends是复数，“镜子”mirror要和主语对应，用复数形式mirrors；
8. 第28空：many后接可数名词复数，“差异”的英文是difference，复数形式为differences；
9. 第29空：固定搭配a sense of humor表示“幽默感”，此处“幽默”用名词humor；
10. 第30空：和quiet并列作表语，“害羞的”对应形容词shy。