33. Nam got wet because He forgot his umbrella.

34. That's very kind of you.

35. Solar energy can be clean and cheap.

36. I look forward to hearing from you.

31. Mr.Phong didn't go to work yesterday because he didn't feel well.

32. I have to do my homeworks, so please turn off the TV.

33. It rained very hard, however, he went out without a raincoat.

34. Please try to speak more loudly and more clearly.

35. I am going to tell you how to keep the environment clean.

36. Most of us discard too much garbage and this dirties our environment.

37. We can reduce this amount by :

- Collecting plastic bags.
- Not keeping solid waste with food waste.
- Putting different kind of waste in different places.

38. If you follow these simple rules.

39. Only you will keep our environment clean,

40. You also save natural resources.

33. Nam got wet because he forgot his umbrella

34. That's very kind of you

35. Solar energy can be clean and cheap(?)

36. I look forward to hearing from you

31) Mr.Phong didn't go to work yesterday because he didn't feel well

32) I have to do my homeworks, so please turn off the TV

33) It rained very hard, however, he went out without a raincoat

34) Please try to speak more loudly and more clearly

35) I am going to tell you how to keep the environment clean

36) Most of us discard too much garbage and this dirties our environment

37) We can reduce this amount by (...)

38) If you follow these simple rules...

39) ...Only you will keep our environment clean

40) You also save natural resources