Babies born in summer are more likely to become short-sighted in late life, a study has shown.

As many as a quarter of all cases of short-sightedness are caused by too great an exposure to sunlight in the first weeks of life, say eye experts.

They are advising all parents to put sunglasses on their babies during the first weeks.

Scientists had already established that over-exposure to sunlight caused short-sightedness in animals.

Researchers who compared the months in which babies were born with whether they needed glasses later on say the principle also applies to humans.

A study of almost 300,000 young adults─the largest of its kind─showed that those born in June and July had a 25 per cent greater chance of becoming severely short-sighted than those born in December or January. Research leader Professor Michael Belkin, of Tel Aviv University, said it was because prolonged illumination(光照) causes the eyeball to lengthen, causing short-sightedness.

Hence the more light a newborn is exposed to, the more the eyeball lengthens and the worse the short-sightedness will be.

The mechanism which lengthens the eyeball is associated with levels of melatonin(褪黑激素), a pigment (色素) which protects the skin against harmful rays of the sun.

In young babies not enough melatonin is released as protection, meaning they are more vulnerable to sunburn and changes to eyeball shape.

Sight expert Professor Daniel O’Leary, of Anglia Ruskin University in Cambridge, said “At the moment we don’t know the precise cause of why light exposure affects sight, but the evidence seems to prove that it is one of the reasons for people becoming short-sighted.”

1.    Babies born in summer are more likely to be short-sighted ____________.

       A. because the summer sun is too strong for babies

       B. because babies born in summer have lengthened eyeballs

       C. if they are exposed to much sunlight in the first weeks after they are born

       D. if parents don’t know a proper way to protect their babies’ eyes

2.    Melatonin is a kind of material to ___________.

       A. prevent the eyes from becoming near-sighted

        B. protect the skin from harmful sun rays

       C. make our body strong

       D. protect babies’ eyes from summer sun

3.      From what Professor Daniel O’Leary says we can conclude that ___________.

       A. there is no evidence that short-sightedness is related to exposure to sunlight

       B. whether light exposure affects sight still needs to be further proved

       C. he believes that light exposure can cause short-sightedness

       D. he tries to give the cause of why light exposure affects sight

4.      The underlined word “vulnerable” in the passage probably means __________.

       A. easy to be harmed                               B. resistant

       C. protective                                             D. changeable

The thief had to admit ________ the car in front of the evidence．

1. A.
   steal
2. B.
   steals
3. C.
   stolen
4. D.
   stealing

Generations of Americans have been brought up to believe that a good breakfast is essential to one's life. Eating breakfast at the start of the day, we have been told, and told again, is as necessary as putting gasoline in the family car before starting a trip.

But for many people, the thought of food as the first thing in the morning is never a pleasure. So in spite of all the efforts, they still take no breakfast. Between 1977 and 1983, the latest year for which figures could be obtained, the number of people who didn’t have breakfast increased by 33%—from 8.8 million to 11.7 million—according to the Chicago-based Market Research Corporation of America.

For those who dislike eating breakfast, however, there is some good news. Several studies in the last few years have shown that, for grown-ups especially, there may be nothing wrong with omitting breakfast. “Going without breakfast does not affect work,” said Arnold E. Bender, former professor of nutrition at Queen Elizabeth College in London, “nor does giving people breakfast improve work.”

Scientific evidence linking breakfast to better health or better work is surprisingly inadequate, and most of the recent work involves children, not grown-ups. “The literature,” says one researcher,  Dr Earnest Polite at the University of Texas, “is poor.”

1.The main idea of the passage is that _______.

2.For those who do not take breakfast, the good news is that _______.

3.The underlined part “nor does giving people breakfast improve work” means  _______.

4.The word "literature" in the last sentence refers to _______.

5.What is implied but not stated by the author is that _______.

The findings come ___36___ a study of nearly 1,000 US people that looked at diet, calorie intake and body mass index (BMI) - a measure of obesity.___37___ is found that those who ate chocolate a few times a week were, on ___38___, slimmer than those ___39___ ate it occasionally. Even though chocolate is loaded with calories, it contains ingredients（材料）that may favour weight loss ___40___ than fat synthesis, scientists believe.___41___ boosting calorie intake, regular chocolate consumption was related to lower BMI in the study, ___42___ is published in Archives of Internal Medicine. The link remained even when other factors, like how ___43___ exercise individuals did, were taken into ___44___.And it appears it is how often you eat chocolate that is important, rather than how much of it you eat. The ___45___ found no link with quantity consumed.

___46___ to the researchers, there is only one chance in a hundred that their findings could be explained by chance alone. Lead author Dr Beatrice Golomb, from the University of California at San Diego, said: "Our findings appear to add to a body of information suggesting that the composition of calories, not just the number of them, matters for determining their ultimate impact on weight."This is not the first time scientists ___47___ that chocolate may be healthy for us. Other studies have claimed chocolate may be good for the heart. Consumption of certain types of chocolate has been linked to some favourable changes in blood pressure, insulin（胰岛素）sensitivity and cholesterol（胆固醇）level. And chocolate, ___48___ dark chocolate, does contain antioxidants（抗氧化剂）which can help to mop up harmful free radicals - unstable chemicals that can damage our cells.

Dr Golomb and her team believe that antioxidant compounds, called catechins（儿茶素）, can improve lean muscle mass and reduce weight  ___49___ studies in rodents would suggest this might be so. Mice ___50___ for 15 days with epicatechin (present in dark chocolate) had improved exercise performance and observable changes to their muscle composition.They say clinical trials are now needed in humans to see ___51___ this is the case.

But before you reach ___52___ a chocolate bar, there are still lots of unanswered questions. And in the absence of conclusive evidence, experts advise caution.While there's no harm in allowing yourself a treat like ___53___ now and again, eating too much might be harmful because it often ___54___ a lot of sugar and fat too.And if you are looking to change your diet, you are ___55___ to benefit most from eating more fresh fruits and vegetables.