根据括号内所给中文写出正确的单词。
1. All my classmates in this school are very _____. (有礼貌的)
2. We have a computer lesson on _____ morning. (星期四)
3. The tall boy over there is good at _____. (游泳)
4. Do you often have dinner at your _____ home at the weekend? (祖父母)
5. There are _____ boys in my class. (二十)
