A Simple Scientific Experiment
| Below is a description of a single scientific experiment. It shows us how iron reacts ( 反应) with air and with water. Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c) in ordinary water. Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner. |
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| Iron in dry air Method (1)Put some iron nails at the bottom of a test tube. (2)Push some cotton wool down the tube. (3)Leave the tube for one week. Result After one week, the nails have not rusted. Conclusion Iron does not rust in dry air. Iron in air-free water Method (1)Half-fill a test tube with water. (2)Boil the water for three minutes. (This makes sure there is no air in the water. (3)Put two or three clean nails in the water. |
(4)Add some oil to the water. (This will keep air out of the water.) (5) Leave the tube for one week. Result The nails do not rust in the tube with air-free water. Conclusion Iron does not rust in air- free water. Iron in ordinary water Method (1)Half –fill a test tube with water and add two or three clean nails. (2)Leave the tube for one week. Result The nails rust in the tube with ordinary water. Conclusion Iron rusts in ordinary water. (238 words) |
In the first part of the experiment the cotton wool is most probably used to ______________.
| A．keep the air dry | B．keep the tube wet |
| C．make the nails rust | D．keep the tube clean |
What are necessary steps to make sure the water in the tube is air free?
①Leave half a tube of water in it
②Boil the water for some time
③Put some clean iron nails in the tube
④Add some oil to the water
| A．①② | B．①③ | C．②③ | D．②④ |
We can conclude from the experiment that only ____________ makes iron rusty.
| A．dry air | B．cotton wool | C．ordinary water | D．air-free water |
Captain James Cook was a great explorer. Before he started exploring, maps of the Pacific Ocean were almost empty. He visited hundreds of islands across the Pacific Ocean and put them in the correct places on the map. He made maps of the coastlines of Australia and New Zealand. James Cook was born in England in 1728. His parents were poor farm workers. When James was 18, he found a job on a coastal ship. He worked on the ship until he was 27 years old, and then he joined the navy. He fought in Canada in a war against France, and he mapped some of the eastern coasts of Canada. In 1768, King George made him Captain(船长) of a ship and sent him to the Pacific. He was gone for nearly three years. When he returned, he was regarded as a national hero.
He started his third journey in 1776. On this trip he visited Hawaii. He was the first European to set foot on this beautiful island. Then he mapped the western coast of North America. After that he returned to Hawaii. Unluckily, there was some trouble between the Hawaiians and the white men and they started fighting. In the end, Captain was killed in a fight against the local.In which order did James Cook do the following things?
a. Fought against France.
b. Mapped the western coast of North America.
c. Was made Captain of a ship.
d. Worked on a coastal ship.
| A．a c d b | B．d a c b |
| C．b a d c | D．d c a b |
He started exploring when _______.
| A．he worked on a coastal ship |
| B．he was 18 years old |
| C．he was sent to the Pacific |
| D．he served in the navy |
He was considered a national hero because of _______.
| A．his experience in Canada |
| B．his being the first European to visit Hawaii |
| C．his heroic death |
| D．his devotion to exploration on the Pacific Ocean |
Captain Cook was killed by _______.
| A．his sailors | B．the Hawaiians |
| C．the Canadians | D．the French |
Have you ever wondered why birds sing? Maybe you thought that they were just happy. After all, you probably sing when you are happy.
Some scientists believe that birds do sing some of the time just because they are happy. However, they sing most of the time for a very different reason. Their singing is actually a warning to other birds to stay out of their territory.
Do you know what a “territory” is? A territory is an area that an animal, usually the male animal, considers as its own. Only he and his family are welcome there. No other families of the same species(物种) are welcome. Your yard and house are your territory where only your family and friends are welcome. If a stranger should enter your territory and frighten you, you might shout. Probably this would be enough to frighten him away.
If so, you have actually scared the stranger away without having to fight him. A bird does the same thing. But he expects an outsider almost any time, especially at nesting(筑巢) season. So he is screaming all the time, whether he can see an outsider or not. This screaming is what we call a bird’s song, and it is usually enough to keep an outsider away.
Birds sing loudest in spring when they are trying to attract a mate and warn others not to enter the territory of theirs.
You can see that birds have a language of their own. Most of it has to do with attracting mates and setting up territories.Some scientists believe that most of the time bird’s singing is actually _____________.
| A．an expression of happiness | B．a way of warning |
| C．an expression of anger | D．a way of greeting |
What does the underlined word “territory” mean?
| A．An area which a bird considers to be its own. |
| B．An area for which birds fight against each other. |
| C．A place where a bird may shout at the top of its voice. |
| D．A place where families of other species are not welcome. |
Why do birds keep on singing at nesting season?
| A．Because they want to invite more friends. |
| B．Because they want to find outsiders around. |
| C．Because they want to express their happiness. |
| D．Because their singing helps frighten outsiders away. |
How does the writer explain birds’ singing?
| A．By telling a bird’s story. |
| B．By describing birds’ daily life. |
| C．By reporting experiment results. |
| D．By comparing birds with human beings. |
Lucy and her classmates are discussing about creating a homepage for their class.
Lucy: What should we put on our class homepage?
Jane: I think our class homepage should have daily or weekly news of class activities.
Mathew: What kind of class activities?
Jane: Something like spring outings, class meetings, a school singing competition, etc.
Mathew: We will go for a spring outing next week, won’t we? I can write something about it.
Lucy: Great! What else should our class homepage have?
Mathew: Um… How about photos of students’ artwork, presentations, and outdoor activities?
Lucy: Good idea! But who will take the photos?
Mathew: As I am a fan of photography, I can take the photos.
Jane: I’ve got an idea. As parents always want to know what assignments their kids do in
and after class, we can also post our weekly agenda(计划表), including in-class assignments and homework assignments, on the homepage.
Lucy: And I think I can create a “reading corner” on the class homepage, too. As I am
a bookworm, I can recommend good books to our classmates.
Jane: Great! Let’s get down to work! _____ is interested in taking photos.
| A．Jane | B．Lucy | C．Mathew | D．No one |
_____ can recommend good books to the classmates.
| A．Lucy | B．Mathew |
| C．Jane | D．No one |
A 90-year-old tortoise (乌龟) is going twice its usual speed after being equipped (装备) with a set of wheels. The animal, called Mrs T, was facing a terrible future after losing her two front legs in a mouse attack while she was sleeping in winter, but her owners glued the wheels onto her shell (外壳).
“She’s going double the speed she used to,” said the owner Jude Ryder, “She uses her back legs to push herself along and seems quite happy.”
The 58-year-old owner was surprised when she went to check on her loved pet last month and found her front legs had been eaten in the mouse attack. The local animal doctor tried his best to save Mrs T. But he was afraid that the tortoise would not survive without being mobile. After paying £1,000 for the treatment, Mrs Ryder turned to her son Dale for help. Dale designed the front wheels and used resin (树脂) to add them to the front of the shell. Mrs Ryder said: “She liked them immediately, but she must learn how to turn and stop. She can get a good speed up, much faster than before. Mrs T is still quite young for a tortoise. She could go on for another 50 years. All she needs is a new set of tyres (轮胎) sometimes.”
When Mrs T was sixty years old, she was bought as a pet for Dale, an 8-year-old boy. It liked running happily in Mrs Ryder’s garden in spring and summer. When winter came, Mrs T slept in the garden shelter. A mouse got in last month and chewed (咬) off both her front legs. Mrs Ryder said: “We were afraid she would be sure to die, but her new set of wheels have saved her life. She can run in the garden again and we can always find her because she leaves very strange footprints behind wherever she goes.”
Mice attacking tortoises is not uncommon around us—in 2013 Britain’s oldest tortoise died after a mouse attack. The tortoise called Thomas was 130 when he was bitten at his home in Guernsey. He spent five days on strong antibiotics (抗生素), but the wound became so infected (被感染的) that his owner had no choice but to have him put to sleep. After being equipped with a set of wheels, Mrs T can move by using .
| A．her back legs to push herself |
| B．her front legs to pull herself |
| C．her back wheels to pull herself |
| D．her front wheels to push herself |
According to the passage, Mrs Ryder’s son is about .
| A．8 years old | B．28 years old |
| C．38 years old | D．58 years old |
Which of the following shows the right order of the story?
a. A mouse chewed off Mrs T’s two front legs.
b. Mrs T’s owners glued the wheels onto her shell.
c. Mrs T learned how to turn and stop with equipped wheels.
d. The local animal doctor tried his best to treat Mrs T.
e. Mrs T was bought as a pet for Dale when she was sixty.
| A．e-a-b-c-d | B．a-b-c-d-e |
| C．a-e-b-c-d | D．e-a-d-b-c |
What can we learn from the passage?
| A．Mrs Ryder is able to move much faster than before. |
| B．Tortoises attacking mice is not uncommon around us. |
| C．The animal doctor added the front wheels to the shell. |
| D．Mrs T can go faster after being equipped with wheels. |
A public primary school in New York City has stopped giving its students homework.
P.S. 116 Principal Jane Hsu wrote a letter to parents last month, explaining that after more than a year of analyzing (分析) studies, the school had decided that students’ after-school time would be better spent on activities like reading at their own pace (步伐) and playing instead of working on homework.
Hsu’s letter says that many studies show that there is no connection between homework and academic (学业的) success. Some other studies also show that the connection between homework and success is dubious at the primary school level.
Harris Cooper, a social psychologist who researches education, found that doing homework makes students perform better in school as they grew older. In later grades, students who did homework performed increasingly better than students who did not. In 2006, Cooper published a study that analyzed 15 years’ worth of data on the influence of homework. He found that homework had a good influence on students as they aged.
Some parents are not happy with the decision to give up homework. “I think they should have homework. I want my daughter to have fun, but I also want her to be working towards a goal,” Daniel Tasman, the father of a second-grader at the school, said to the reporter.
“Students have to do homework in order to gain. Students have to do homework because they may not be able to understand everything in school,” Sharon Blake, a student’s grandmother told ABC news.
The passage is probably from a .
| A．newspaper | B．comedy | C．cartoon | D．novel |
Jane Hsu wrote a letter to parents to explain .
| A．how students should read at their own pace |
| B．what activities students could take at home |
| C．why the school gave up homework recently |
| D．how important the homework is for students |
The word “dubious” in Paragraph 3 probably means “not ”.
| A．clear | B．public | C．real | D．special |
What can we infer (推断) according to the passage?
| A．Cooper found homework had a bad influence on students as they aged. |
| B．Some parents are worried about their children if there is no homework. |
| C．Some students are not happy with the decision to give up school homework. |
| D．Daniel Tasman wanted his daughter to have fun instead of working to a goal. |