题目内容

Where did humans come from? An Australian researcher believes that she’s found the answer: river valley in the African country of Botswana (博瓦纳).

Professor Vanessa Hayes from the Garvan Institute of Medical Research in Sydney said she and her team have traced (追踪) modern humans back to small group of people who lived in this valley, according to the BBC.

“It’s an extremely large area, it would have been very lush (苍翠繁茂的), and it would have actually provided a suitable habitat for modern humans,” she said. She and her team studied mitochondrial (线粒体的) DNA (mtDNA) from people who live in south Africa, such as the Khoisan people. This type of DNA is only passed down from mother to child. This makes it easier to trace one’s ancestry (祖先), according to Business Insider. By tracing mtDNA back through different generations, the team concluded that every person alive today is related to a woman who lived in Botswana.

However, some experts doubt Hayes’ findings, saying that studies like hers are no longer important or necessary. “The idea that we’re looking for a single origin [of modern humans] is out of fashion,” said John Hawks, a researcher at the University of Wisconsin-Madison, US, in Popular Science.

There are many other locations around the world where humans could have gotten their start. It is likely that mankind appeared in many places at the same time. “I increasingly think that there probably wasn’t a single population in which modern humans evolved (进化). If that is the case, there is no ‘homeland’,” said Ryan Raaum, who researches African population genetics (遗传学) at Lehman College, US.

1.According to Hayes, where did humans come from?

A.Australia. B.Botswana. C.South Africa. D.Latin America.

2.Hayes and her team studied mtDNA because ________.

A.it is the most common type of DNA humans share B.there is a new technology to test mtDNA

C.it is only passed down from mother to child D.both women and men can take mtDNA tests

3.According to Hawks, Hayes’s study is ________.

A.important B.wrong C.fascinating D.unnecessary

4.What is the story mainly about?

A.New findings about the origin of humans. B.New findings about mtDNA.

C.The evolution of humans. D.The habitats of ancient humans..

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I live in a nice new building in Beijing. It is very tall. It has eighteen floors. There are about eighty families in the building. That is to say (也就是说), about two hundred and forty people live in the building.

My home is on the twelfth (第十二) floor. We have two bedrooms and a living room. They are big and clean. There are a lot of big trees and beautiful flowers around our building. I like looking out of the window in my room. I can see cars and buses running in the street. I can see people walking in the street, too. They look so small! I can also see a lot of tall buildings. How beautiful Beijing is! I am happy to live in this nice, new and tall building.

根据短文内容，选择正确答案。

1.There are ________floors in the building.

A.twelve B.twenty C.eighteen D.eighty

2.How many people are there in the building?

A.Two hundred. B.Three hundred.

C.Two hundred and forty. D.About two hundred and forty.

3.There are many ________ around the building.

A.cars B.big trees and beautiful flowers

C.shops D.buses

4.What can I see from the window in my room?

A.I can see cars and buses running in the street. B.I can see people walking in the street.

C.I can see a lot of tall buildings. D.A, B and C.

5.Which of the following is NOT true?

A.The building is tall. B.There are a lot of birds around the building.

C.Beijing is very beautiful. D.The building is new.

—Don't worry, madam. Your shopping bag _______ here until you come back.

—Thank you very much.

A.was kept B.has kept C.keeps D.will be kept

We improved the situation by stopping factories from putting waste into the rivers. (对画线部分提问)

________did you________the situation?

The museum is open every day________ (除了) Monday.

—Would you like me to help you with the homework?

— . But I can manage it myself.

A.It doesn’t matter B.The same to you

C.It's very kind of you. D.Never mind

It's the museum! So you know shouting is not allowed here.

A.can B.could C.must D.may

No matter how old your kids are, you can take steps to improve a healthy diet and to encourage good eating habits.

Tip One: Family Meals

Family meals are nice for both parents and kids. Children like to guess what they are going to have and parents get the chance to introduce new foods to children. Parents can also use the mealtime as a chance to talk with their kids about their life.

Tip Two: Healthy Snacks

Kids, especially younger ones, will eat mostly what can get at home. That’s why it’s important to have enough healthy snacks, such as fruits, vegetables, nuts, yogurt and whole-grain biscuits.

Tip Three: Being a Good Example

The best way for you to encourage healthy eating is to eat well yourself. Kids will follow the lead of the adults they see every day. By eating fruits and vegetables and avoiding fast food and sweet drinks, you are sending the right message.

Tip Four: No Shouts about Food

Parents might find themselves shouting at children to get them to have healthy foods in front of them. This in fact can make children dislike what they are asked to eat. You need to work a bit on different cooking methods.

Tip Five: Get Kids Included

Most kids will enjoy making the decision about food. Talk to them about making choices and planning a healthy meal. It can help them to make good decisions on their own about the foods they want to eat.

1.The author’s attitude(态度) toward snacks is ________.

A.snacks shouldn’t be eaten B.healthy snacks can be accepted

C.kids can only have snacks at home D.it’s not necessary to have snacks at home

2.The best way for parents to encourage a healthy diet is ________.

A.to have family meals B.to eat healthy snacks

C.to be a good example D.to get kids included

3.According to Tip Four, parents should ________ if kids refuse to eat healthy food.

A.explain how healthy it is B.try cooking it in a different way

C.never cook the same food D.ask kids to get used to its taste

4.Parents should get kids included ________ when they make the decision about food.

A.to let kids eat anything they like

B.to help kids become a wonderful cook

C.to help kids make good choices by themselves

D.to set a good example of eating healthy food

-Susan, would you like another cake?

-_______________. I'm full.

A.Yes, please B.My pleasure C.No, thanks D.Not at all

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