21.　 You were supposed to meet at the bus stop this morning to return it, but A didn’t come to the bus stop.　

20.　 You are at B’s house working on a homework project.　

19.　 She now works as a math teacher at a high school in the city of 　Pingliang　, 　Gansu　 　Province　.　

18.　 She said she likes being a good influence in the children’s lives.　

17.　 I can open up my students’ eyes to the outside world and give them a good start in life.　

16.　 Some of the students may not be able to go to senior high school or collage.　

15.　 Young people today need to experience different things　

14.　 Life in the mountains was a new experience for Lang Lei. Her village was 2,000metere above the sea level, and at first the thin air made her feel sick.　

13.　 The 　Peking　 　University　 graduate first went there as an volunteer on a one-year program.　

12.　 Teaching high school students in a poor mountain village in 　Gansu　 　Province　 may not like fun to you.