题目内容

________ to sunlight for too much time will do harm to our skin．

A.
Exposed
B.
Having exposed
C.
Being exposed
D.
After being exposed

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arrange inform of break down put forward delight

concentrate on take up contribute to expose accuse of

The suggestion ________________ by the chairman was rejected at yesterday’s meeting.

_____________ to sunlight for too much time will do harm to your skin.

Doing sports on a regular basis _____________ our health.

His car __________ constantly ___________, which makes him crazy especially when he is in a hurry.

In order to calm their child down, the mother _____________ the story where the father left off the night before.

______________ to live in the countryside, he has never thought of seeking fortune in the big cities.

He couldn’t ____________________ his experiment with so much noise going on outside the labs.

Being afraid of falling behind the times, he has always been keeping himself ____________ the latest development of technology.

The young man _________________ stealing three times since he left high school.

He demanded that a car _______________ to pick him up at the airport.

_____ to sunlight for too much time will do harm to one’s skin.

　 A. Exposed 　 B. having exposed

　 C. Being exposed 　 D. After being exposed

Vitamin D helps bones and muscles grow strong and healthy. Low levels of vitamin D can lead to diseases such as rickets (佝偻病), mainly found in children. The thinning of bone is a common problem as people, especially women, get older.
But more and more research is suggesting that vitamin D might also help prevent many diseases. The easiest way to get vitamin D is from sunlight. The sun’s ultraviolet (紫外线的) rays react with skin cells to produce vitamin D. But many people worry about getting skin cancer and skin damage from the sun. As a result they stay out of the sun. Also, darker-skinned people produce less vitamin D than lighter-skinned people. The amount also decreases in older people and those living in northern areas that get less sunlight.
Not many foods naturally contain vitamin D. Foods high in this vitamin include oily fish and fish liveroils (鱼肝油). Farmed fish have only about one-fourth as much vitamin D as wild fish. Small amounts of vitamin D are found in beef liver, cheese and egg yolks. But most of the vitamin D in the American diet comes from foods such as milk.
Research in the last several years has shown that low levels of vitamin D may increase the risk of heart attacks in men and deaths from some cancers. More doctors are now having their patients tested for their vitamin D levels. But as research continues, some experts worry that if people take too much vitamin D, it might act as a poison. Also, skin doctors warn people to be careful with sun exposure because of the risk of skin cancer.
【小题1】The first paragraph is mainly about 　　　　.

A．the muscle diseases	B．the sources of vitamins
C．the importance of health	D．the functions of vitamin D

【小题2】Which of the following people produce the least amount of vitamin D?______

A．Elderly darker-skinned people.	B．Young lighter-skinned people.
C．Elderly lighter-skinned people.	D．Young darker-skinned people.

【小题3】 People can get the most vitamin D from 　　　　.

【小题4】What can we infer from the text?_________
A. Being exposed to sunlight is the safest way to get vitamin D.
B. Lack of vitamin D can make people age quickly.
C. Proper vitamin D levels people need are still not determined now.
D. The vitamin D level is higher in men than in women.

A healthy dose of sunshine may be the secret to staying young, British scientists have disclosed.

Vitamin D is produced naturally by the skin in response to sunlight and may help to slow the ageing process and protect against heart disease, according to the study.

Researchers from King's College London studied 2,160 women aged between 18 and 79, looking at their telomeres - a biological marker of ageing found in DNA．As people get older, their telomeres get shorter and they are easy to have illnesses.

But the study found women with high levels of vitamin D had comparatively longer telomeres - a sign of being biologically younger and healthier.

The study suggests vitamin D may help to slow down the ageing process of DNA, and therefore the ageing process as a whole.

Lead researcher Dr Brent Richards said: "These results are exciting because they prove for the first time that people who have higher levels of vitamin D may age more slowly than people with lower levels of vitamin D．

"This could help to explain how vitamin D has a protective effect on many ageing related diseases, such as heart disease and cancer."

He said further studies are required to confirm the findings.

Professor Tim Spector, head of KCL's twin research unit, and a co-author of the report, added: "Although it might sound absurd(荒谬的), it's possible that the same sunshine which may increase our risk of skin cancer may also have a healthy effect on the general ageing process."

Vitamin D made by the action of sunlight on the skin accounts for 90 per cent of the body's supply, but lower levels can also be obtained through food such as fish, eggs and breakfast cereals.

Other studies have suggested the vitamin plays a key role in protecting against cancer and heart disease.

1.What’s the best title of this passage?

A.Sunshine helps to keep you young.

B.Vitamin D has a protective effect on many diseases.

C.Telomeres - a biological marker of ageing.

D.People have found the secret to having a long life.

2.How can people get Vitamin D?

A.through water. B. through sunshine.

C.through food. D.both B and C.

3.Which of the following is not true according to the passage?

A.women with high levels of vitamin D shows a sign of being biologically younger and healthier.

B.vitamin D has a protective effect on many ageing related diseases.

C.too much sunshine may increase our risk of skin cancer.

D.It has been proved that sunshine helps to keep you young.

CHICAGO （Reuters） - Smoking not only can wrinkle （起皱纹） the face and tarn it yellow—it can do the same to the whole body, researchers reported on Monday．

The study, published in the Archives of Dermatology, shows that smoking affects the skin all over the body—even skin protected from the sun．

"We examined non - facial skin that was protected from the sun, and found that the total number of packs of cigarettes smoked per day and the total years a person has smoked were linked with the amount of skin damage a person experienced," Dr．Yolanda Helfrich of the University of Michigan, who led the study, said in a statement．

"In participants older than 65 years, smokers had significantly more fine wrinkling than nonsmokers．Similar findings were seen in participants aged 45 to 65 years," Helfrich "s team added in their report．

The researchers tested 82 people, smokers and nonsmokers, taking pictures of the inner right arms． They ranged, in age from 22 to 91 and half were smokers．Independent judges decided how wrinkled each person' s skin was．

When skin is exposed to sunlight, notably the face, it becomes coarse, wrinkled and discolored with a pale yellow tint, Helfrich ' s team wrote．

Several previous studies have found that cigarette smoking contributes to premature（过早的）skin aging as measured by facial wrinkles, the study said, but little has been done to measure the aging of skin not exposed to light．

The report did not discuss die mechanism involved but previous research has found that cigarette smoke, among other things, causes blood vessels （血管） beneath the skin to constrict （紧缩）, reducing blood supply to the skin．

Smoking can also damage the connective tissue that supports both die skin and the internal organs,．

1.When your skin is exposed to sunlight long, it-becomes all of the following but _____．

A．flexible B．coarse C．rough D．discolored

2.How wrinkled a person's skin is doesn't relate to _____．

A．the number of cigarettes a person smokes．

B．the kind and characteristics of skin

C．how long a person smokes

D．how long skin is under sunlight

3.From the passage smoking results in skin aging mainly because _____.

A．it will lower blood supply to skin

B．it can make you feel tired

C．it can make skin come off

D．it can make blood run faster

4.The main purpose of the passage is to _____．

A．inform people about the result of the study

B．advise people how to protect skin

C．warn people not to smoke again

D．introduce a new way of avoid skin aging

________ to sunlight for too much time will do harm to our skin．

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