18. activity / after-school activities (pl.)

17. competition(s)

16. high (adj.)----height (n.)　　 long ----length (n.)　　 weigh (vt.)----weight (n.)

15. cheer (v.)---- cheerful (adj.)----cheerfully (adv.)

14. true (adj.)---- truly (adv.) ---- truth (n.)

13. advertise (vt.)---- advertisement (n.)

12. fit (vi) 被容纳 (v.)适合This pair of shoes fits me well.　

(adj.)合适的be fit for…/ be fit to do sth.

(adj.)健康的 = healthy

11. play a joke/ trick on sb.

10. bore (v.) ---- boring / bored (adj.)

9. have a (good) sense of humour = be humourous