- Con người nói chuyện với nhau (truyền qua chất khí).

- nghe nhạc ( truyền qua chất khí )

âm truyền được trong môi trường : chất rắn, chất lỏng, chất khí

môi trường truyền âm tốt là khí

vd: 

+ Bạn A dùng đầu bút gõ xuống mặt bàn, bạn B áp tai vào bàn nghe được âm thanh do âm truyền trong gỗ. Âm truyền được trong chất rắn.

+Thả một chiếc đồng hồ báo thức được bọc nilong (ngăn thấm nước) vào trong bể nước. Ta vẫn nghe được tiếng chuông báo do âm truyền trong nước. Âm thanh truyền được trong chất lỏng.

+ Cô giáo giảng bài, các học sinh ngồi trong lớp đều nghe được lời cô giảng do âm truyền trong không khí. Âm thanh truyền được trong chất khí.

1. It‟s a pity John can‟t come to my birthday party this weekend. 
(Rewrite the following sentences using “I wish “construction).
→ I wish……………………………………………………….
2.  I’m sorry I don’t have time to go to the cinema with you.( Use:” I wish”)
→ I wish ………………………………………………………………….
3. he/ used/ play/ football/ local team,/ but/ he/ too/ old/ now. 
(Write sentences, using the clues given)
→ - He used to …………………………………………………………..
 4.I had saved my document before the computer crashed. ( Use: AFTER)
→ After I had………………………………………………… .
5.This was my favourite bicycle. I rode everywhere on it( Use : “used to+ V1”)
→ This was my favourite bicycle. I used ………………………………
6.I/ suggest/ that/raise/ money/charity( Make a complete sentence)
→ I suggest that ………………………………………………………….
7.The traffic problems of the city had been solved. The Prime Miniter was pleased.
(Use: S+ be+ adj+ that-clause)
→ The Prime Miniter was ……………………………………………………………. 
8.I am sorry about the school facilitiesour parents had. They are very poor.
(Use: S+ be+ adj+ that-clause)
→ - I am sorry that ……………………………………………………………

25.  The teacher asked me __________ worried about before the exam.

A. What I am most                                                      B. what I am     

C. what most I was                                                D. what I was most     

26. She wishes she ______ a longer summer vacation.

A. can have                                                           B. could have          

C. is having                                                                 D. has

27.  I doubt that you can’t understand her situation and help her feel better.

A. believe        B. suspect            C. compete          D. advice

28. I wish the school authorities can set holidays based on local weather conditions.

A. authorities        B. can              C. based on      D. conditions 

29. Before the movie Kong: Skull Island  was releases, not many people  __________

A. knew B. have known C. known D. had known

30. It was reported that five people  __________ in the car crash.

A. had been injured B. were injured C. have been injured D. injured

19. She ______ a teddy bear, but she doesn't have one now. 

A. used to have         B. used to having      C. was use to having  D. was used to have

20. When we were in Da Nang, we spent a lot of time  __________  around and looking at the ancient temples, bridges and houses.

A. wander            B. wandering              C. wandered                   D. wanders

21. On children Festival, the zoo is always   __________ with people mainly children.

A. packed             B. had               C. contained                   D. scored

22. You should take your shoes  __________  when you go into the temples.

A. up              B. in                    C. off                      D. on

23. When the doctor came in, he went  __________   all my test results and gave me a prescription.

A. out           B. over                 C. in                       D. of

24.  The woman asked ________ get lunch at school. 

A. can the children                                      B. whether the children could

C. if the children can                                              D. could the children

13. _________ less meat is better for the environment.

A. Eat B. Eating C Ate D. To eat

14. They wished that time will be turned back so that they could go kite-flying with other kids.

A. wished        B. will be turned          C. could go      D. kite-flying

15.  I have a lot of work to do. I wish I to have more time.

A. have            B. a lot            C. to                D. to have

16. It ______ that learning English is easy.

A. are said                  B. is said                               C. said                D. say

17. It was stupid of you __________ the road without looking left and right.

A. to crossing  B. crossing      C. to cross        D. cross

18. It is important that we _______ the instructions carefully before taking medicince.

A. to follow    B. follow          C. followed      D. following