【单选题】
超声波的波长___。
A. 与速度和频率成正比
B. 与速度成正比与频率成反比
C. 与速度成反比与频率成正比
D. 等于速度和频率的乘积
查看试卷，进入试卷练习
微信扫一扫，开始刷题
答案
B
解析
暂无解析
相关试题
推荐试题
【单选题】
11. When the parents arrived at the hall, the students _______ their projects.
A. have finish B. finished C. had finished D. are finishing
A. A
B. B
C. C
D. D
【单选题】
12. This week, the _______ seems to change every day: one day is hot; the next day is cold.
A. time B. weather C. season D. way
A. A
B. B
C. C
D. D
【单选题】
13. He never does his work _______ Mary.
A. as careful as B. so careful as C. carefully as D. as carefully
A. A
B. B
C. C
D. D
【单选题】
14. — Can he jump high?
— Yes, he ______. He is a good high jumper.
A. must B. need C. can D. shall
A. A
B. B
C. C
D. D
【单选题】
15. The shop _____ at 8:00 a．m．and it ________ for ten hours every day．
A. is open; has opened B. is opened; opens
C. opens; is open D. opened; opens
A. A
B. B
C. C
D. D
【单选题】
16. —Excuse me, may I use your bicycle? ______ is broken.
Certainly. But remember to return it before lunch.
A. Mine B. Me C. Myself D. I
A. A
B. B
C. C
D. D
【单选题】
17. Simon, what do I need to take for the hiking?
Youd better ________ more water than usual. Its hot today.
A. to take B. taking C. take D. took
A. A
B. B
C. C
D. D
【单选题】
18. Helen ______ to a language school when she was seven.
A. sent B. is sent C. will send D. was sent
A. A
B. B
C. C
D. D
【单选题】
19. — Is this park youve visited recently?
— Yes, it's the most beautiful one Ive ever visited before.
A. that B. the one C. which D. the one which
A. A
B. B
C. C
D. D
【单选题】
20. — Its difficult for the village children to cross the river for school.
— I think a bridge ________ over the river.
A. should be built B. is being built C. has been built D. was built
A. A
B. B
C. C
D. D
【单选题】
21. — Could you tell me when Mr. Li ________ in Huaibei?
— Sure．．When he ________, I’ll call you．
A. arrives; will arrive B. will arrive; will arrive
C. arrives; arrives D. will arrive; arrives
A. A
B. B
C. C
D. D
【单选题】
22.There is ________ 800-metre-long road behind ________ hospital．
A. an; an B. an; the C. a; a D. a; the
A. A
B. B
C. C
D. D
【单选题】
23. — Did you see a girl in yellow pass by just now?
— No, sir. I ________ a magazine.
A. read B. am reading C. was reading D. would read
A. A
B. B
C. C
D. D
【单选题】
24.In fact, my parents are not only kind to me, but also strict ________ me.
A. at B. to C. for D. with
A. A
B. B
C. C
D. D
【单选题】
25. The boy_____ a yellow sweater can_____ himself now．
A. wearing; dress B. putting on; wear C. put on; dress D. dressing;
A. A
B. B
C. C
D. D
【单选题】
( ) 26. Where does the writer of "The little Prince" come from?
A．England． B．France． C．America． D．China．
A. A
B. B
C. C
D. D
【单选题】
( ) 27. What does the prince do after the fox tells him a secret?
A．He cares more about a flower and a sheep．
B．He meets many more strange adults on other planets．
C．He realizes his love for the rose and he goes back to his planet．
D．He discovers interesting things such as a snake, other roses and a fox．
A. A
B. B
C. C
D. D
【单选题】
( ) 28. What does "The little Prince" mainly talk about? It' s about _________．
A．the adult world B．the planet B -612
C．a rose and a fox D．the adventure of a young
A. A
B. B
C. C
D. D
【单选题】
( ) 29. When a baseball player hits the ball, he must ______ to get a point.
A. run to each base freely
B. touch the home plate first
C. touch all the bases with his hands
D. run to each base in order and touch it with his foot
A. A
B. B
C. C
D. D
【单选题】
( ) 30. When was the importance of touching all the bases shown?
A. Before the baseball rules made.
B. At the end of the 1974 baseball seasons.
C. At the start of the 1974 baseball seasons.
D. In the second week of 1974.
A. A
B. B
C. C
D. D
【单选题】
( ) 31. Who hit home run number 715?
A. Babe Ruth. B. Hank Aaron. C. Babe Ruth’s partner. D. Hank Aaron’s friend.
A. A
B. B
C. C
D. D
【单选题】
( ) 32. What does the expression “to touch all bases” mean?
A. To try your best to set a new record.
B. To get a chance to be the greatest hitter.
C. To do what is needed to finish an activity.
D. To solve the problems successfully.
A. A
B. B
C. C
D. D
【单选题】
( ) 33. The Chinese Yellow Sea Wetlands are in the _______ of China．
A．south B．east C．west D．north
A. A
B. B
C. C
D. D
【单选题】
( ) 34. Usually the weather in the wetlands is _______．
A．hot B．pleasant C．cold D．dry
A. A
B. B
C. C
D. D
【单选题】
( ) 35. The World Wetlands Day is on _______．
A．February 2 B．June 25 C．April 22 D．March 22
A. A
B. B
C. C
D. D
【单选题】
( ) 36. We must protect wetlands because _______．
A．they are home for wildlife B．they can prevent flood
C．they can offer food to the animals and birds D．all of the above
A. A
B. B
C. C
D. D
【单选题】
( ) 37.The greatest river for navigation is ___________.
A. the Nile B. the Amazon C. the Mekong D. the Mississippi
A. A
B. B
C. C
D. D
【单选题】
( ) 38. From a dam, people can use the water for ___________.
A. keeping the rivers clean B. only making electricity
C. irrigation and making electricity D. washing clothes
A. A
B. B
C. C
D. D
【单选题】
( ) 39. The water in the river is polluted because of _____________.
A. people's drinking water too much B. people's swimming in the river too much
C. chemicals and other materials D. people's building a dam across a river
A. A
B. B
C. C
D. D
【单选题】
( ) 40. The best title of the passage is ___________.
A. Rivers in Cities B. The importance of Rivers
C. Transportation D. Natural Resources
A. A
B. B
C. C
D. D
【单选题】
1.—Hello! This is Henry Speaking．I’d like to speak to your father．
—Sorry, he has Shanghai．
A. been in B. been to C. come to D. gone to
A. A
B. B
C. C
D. D
【单选题】
2. — It’s difficult for the village children to cross the river for school．
— I think a bridge ______ over the river．
A. was built B. is being built C. has been built D. should be built
A. A
B. B
C. C
D. D
【单选题】
3. —Where would you like to go, Jinan or Qufu?
— ．I only want to go to Qingdao．
A. Each B. Either C. Neither D. All
A. A
B. B
C. C
D. D
【单选题】
4. — The documentary A Bite Of China II is quite popular around China recently. How do you like it? — ______.
A. I think so B. Pretty good C. It’s my pleasure D. All right
A. A
B. B
C. C
D. D
【单选题】
5. There are three English-books on the shelf, but ______ of them is mine.
A. both B. neither C.all D. none
A. A
B. B
C. C
D. D
【单选题】
6. When the parents arrived at the hall, the students _______ their projects.
A. have finish B. finished C. had finished D. are finishing
A. A
B. B
C. C
D. D
【单选题】
7. This week, the _______ seems to change every day: one day is hot; the next day is cold.
A. time B. weather C. season D. way
A. A
B. B
C. C
D. D
【单选题】
8. He never does his work _______ Mary.
A. as careful as B. so careful as C. carefully as D. as carefully as
A. A
B. B
C. C
D. D
【单选题】
9. — Can he jump high?
— Yes, he ______. He is a good high jumper.
A. must B. need C. can D. shall
A. A
B. B
C. C
D. D
【单选题】
10. The shop _____ at 8:00 a．m．and it ________ for ten hours every day．
A. is open; has opened B. is opened; opens
C. opens; is open D. opened; opens
A. A
B. B
C. C
D. D
