网址:http://m.1010jiajiao.com/timu3_id_2405872[举报]
1
Three kids have been learning chemistry for only a few months. But they have already begun to challenge (挑战) a world famous scientist!
Li Weichi, Huang Runling, and Xiao Yan are from Zhongshan Huaqiao Middle School in Guangdong. They have just found a red cabbage that could be a new kind of acid-base indicator (酸碱指示剂). They want it to take the place of litmus (石蕊) paper.
"We've learnt to think of and ask questions about life by ourselves," said Li, "We work well with each other."
British scientist Robert Boyle discovered the use of litmus paper over 300 years ago. Now it is used widely in experiments all over the world.
But when the kids did some experiments in class last winter, they saw that the litmus paper didn’t turn very blue with base matter. It's hard to get a clear result.
Will there be a better indicator than litmus paper? The three kids decided to try and find out!
How? They went to collect over 40 plants in parks, gardens and markets. Then they ground (研磨) leaves, flowers and stems (茎) to get the pigments (色素) from them.
The kids mixed pigments with acid and base. They spent months watching carefully to see which paper showed the best color change. They decided it was the litmus paper!
"It's our first scientific journey, Huang said, "But it makes me want to try harder."
1.Whom did the three kids want to challenge?
A. Their chemistry teacher.
B. Their headmaster.
C. Robert Boyle
D. Thomas Edison
2.From the text, a red cabbage is a kind of ____.
A. plant B. animal C. paper D. liquid
3.What is widely used as the acid-base indicator now?
A. red cabbage B. litmus paper
C. any plant D. any flower
4.The story mainly tells us ____.
A. how to make litmus paper
B. about the three kids' spirit
C. scientists were wrong
D. the kids are heroes
查看习题详情和答案>>
In a small town in France, there was a farmer who lived alone. Every day he 31 a pound of butter to his neighbour, who was a baker, One day the baker decided to 32 the butter to see if he was getting a pound. After he weighed it, he found that he wasn't. The baker then took 33 farmer to the judge (法官).
The judge asked the farmer if he had any way to weigh the butler. The farmer replied. "I am so 34 that I do not have enough money to buy anything to weigh it, 35 I do have a kind of scale(天平). " The judge asked, "Then how do you weigh the buttery" The farmer replied, "Before the baker started buying butler from 36 , I had bought bread from him. So now every time when I bring home the bread from the baker, I put it On the scale and give him the butter of the same weight,"
We 37 what we give to Others in life. Whenever you take action, ask yourself this 38 , "Am I honest?"
Honesty or dishonesty can become a 39 . Some dishonest people can lie(说谎) without a red face. Others lie so much that they do not even 40 what the truth is any more. But who is it bad for? As a matter of fact, those who lie will hurt themselves by their own dishonest behaviour.
31. A. gave B. fed C. threw D. sold
32. A. weigh B. watch C. cut D. use
33. A. / B. a C. an D. the
34. A. rich B. poor C. honest D. quiet
35. A. and B. so C. but D. or
36. A. I B. my C. me D. mine
37. A. get back B. look back C. give back D. turn back
38. A. answer B. question C. help D. idea
39. A. difference B. habit C. mistake D. difficulty
40. A. Study B. mean C. imagine D. know
查看习题详情和答案>>It's not just women who wear skirts. Men can wear them, too. In Scotland, men wear a kind of skirt called a kilt. The kilt is their national dress and an important part of their tradition (传统).
A kilt is a colored skirt reaching down to the knees(膝盖). It has checks (格子) on it with different colors, like red or blue. Each family in Scotland has its own colors.
How did the Scots start to wear kilts? There are many stories about it. One story is that the kilt was invented (发明) in the 1720s by an English factory owner, Thomas Rawlinson. Rawlinson had a lot of Scottish workers in his factory and he thought their clothing got in the way of their work. So he cut their long clothes into a shorter skirt.
Today, most Scotsmen see kilts as formal(正式)dresses. They usually only wear them at weddings or big dinners. There are only a few men who still wear a kilt every day. Scots also wear kilts in parades when they play their traditional musical instrument(乐器): bagpipes (风笛). The army still has kilts as the dress uniform (制服), but they no longer wear them to fight (打仗).
1. A kilt is ____.
A.
B.
C.
D.
2.In Scotland, different families have different ___.
A. colors B. checks C. rules D. shapes
3.What does "got in the way of" in the third paragraph mean?
A. 到达 B. 得到 C. 在路上 D. 妨碍
4.When do Scotsmen wear kilts?
A. At weddings B. At big dinners C. In parades D. all of the above
5.The story mainly tells us ____.
A. things about Scotsmen's traditional kilts
B. how to wear kilts
C. when to wear kilts
D. Scotsmen's important tradition
查看习题详情和答案>>
As everyone knows, there are many 16 of transportation in the world, like bicycles, buses, ships, trains and 17 .
If you are in big 18 like Shanghai or Beijing, maybe you get to school 19 a subway or you have to 20 to school because you live in a mountain village. Here I am just trying to say something about 21 .
Ten years 22 , bicycles were very 23 in most villages. 24 family had one or two of bicycles. Children got to school by bicycle; 25 rode bicycles to go shopping. Then motorcycles (摩托车) 26 to become popular. People no longer rode bicycles because motorcycles ran 27 faster. But now, in some countries,bicycles are highly suggested
28 the main means of transportation. They think buses, cars and motorcycles pollute(污染) the air but bicycles 29 . So, to live a low-carbon life, 30 a bike is a good way.
1. |
|
2. |
|
3. |
|
4. |
|
5. |
|
6. |
|
7. |
|
8. |
|
9. |
|
10. |
|
11. |
|
12. |
|
13. |
|
14. |
|
15. |
|
查看习题详情和答案>>
|