1 . As scientists probe(探究) the mysteries inside our heads, their discoveries are proving new insights into how we can all sharpen our mental machinery.

Your brain is fat

In fact, you brain is the fattiest organ in your body, consisting of a minimum of 60 percent fat. Fat carries, absorbs and stores vitamins in your bloodstream.    1    .

We can get smarter as we get older

Rawan Tarawneh, an assistant professor, points out that although some mental processes decline as we age, not all does.    2    , On the other hand, language functions tend to remain well preserved as we get older, peaking even into our early 70s.

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Comparing the brains of great thinkers, writers, and mathematicians hasn’t yielded conclusive evidence that the size of the brain has a connection to intelligence.

Intelligence might start with ignoring distractions

Intelligent people were better at detecting movements of small objects on a screen but worse at movements of large background objects. This may be because in nature, large movements such as the wind in the trees are irrelevant, but the harder-to-see animals is essential.    4    

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For example, experiments have shown that people who were born blind use the visual parts of their brains for tasks other than seeing.

A．Fat is essential for brain.

B．In our information-laden world, focusing on only what’s important may give some people an edge (优势).

C．The close connection between brain’s size and intelligence.

D．It also helps the immune system function properly.

E．You brain can adapt itself.

F．Some of our brain functions, such as short term memory show some decline with aging.

G．Bigger isn’t necessarily better.

2 . “Could your weekend lie-in(睡懒觉) kill you?, asked the Daily Mail. It is said in a study that sleeping more at weekends can increase the risk of heart disease. Since most of us change our sleep schedule depending on whether it’s a work or non-work day, it’s an interesting question. Is the lie in really so dangerous? Researchers say that changing sleep pattern cause social jet lag. Is that even a thing?

Changing our sleeping hours causes the effect of crossing a time zone-it makes us sleepy the day. People who changed their sleep patterns were also more likely to gain weight during the study and more suited to going to bed and waking late because of the change of their biological clock. They were more at risk of these changes than earlier sleepers and risers. The study also shows an association switching sleep patterns and changes in some blood results. It does not show that anyone’s developing heart disease was because they had lie-ins.

Jim Horne, one of the professors of the Sleep Research Center, says the concept of social jet lag is likely to feed our anxiety about sleep, so we should really stop worrying so much and have a limited weekend lie-in. Worry is bad for sleep and we naturally compensate for not getting enough rest in the week by lying-in at weekends, so we shouldn’t stop doing it. However, we should limit the time.

Studies show that if you accumulate a five-hour sleep debt during the week, then you only need one and a half hours of extra sleep on your days off to make up for it. It would be a shame to be scared of lie-in. Studies of sleep and risk factors for heart disease can struggle to tell between poor sleep causing stress and stress disrupting sleep. Sleep is the test for the state of one’s health, and the most important thing that happens when you don’t get enough of it is that you feel sleepy.

1. What’s the consequence of switching sleep patterns?

A．You’ll feel more energetic.

B．Some blood results will change adversely.

C．You will become earlier sleepers and risker.

D．The chance of putting on weight will enhance.

2. What does the underline phrase “doing it” refer to?

A．Lying-in.	B．Worrying.
C．Limited Sleeping.	D．Compensating for the limit.

3. What is Horne’s attitude to the weekend lie-in?

A．Negative.	B．Doubtful.
C．Ambiguous.	D．Supportive.

4. What can we infer from the text?

A．The sleep debt should be paid off completely.

B．The weekend lie-in is more healthy than harmful.

C．Social jet lag occurs when you don’t get enough sleep.

D．Poor sleep may result from and cause stress in turn.

3 . Alibaba co-founder and chairman Jack Ma on Monday announced in an open letter that he would step down, with the company CEO Daniel Zhang taking over as the chairman of the board. Zhang, is known as a key architect of Alibaba’s “Singles Day”, the Nov. 11 event that has become the world’s largest online shopping event. In the letter entitled “Happy Teachers’ Day,” Ma said he would retire as the chairman of the board on Sept. 10, 2019. Ma said he would work closely with Zhang to ensure a smooth transition and stay on the Alibaba board of directors until the annual shareholders meeting in two years. After he steps down, he will continue to be part of the “Alibaba Partnership”, which has the ability to nominate the majority of directors on the company’s board. He also wants to return to education and charity, which gives him excitement and blessings.

“There’s only Bill Gates who has done the same. No other tech founder in the world has just resigned like that at the top,” said Rupert Hoogewerf, which publishes an annual influential list of China’s richest people. Hoogewerf added that in China, Ma was a figure like no other, with friends ranging from movie stars to billionaires, though he often outshone them all. “He’s the big one, he’s the one that brings them together.”

The company was founded at a time when the industry was still dominated by state-owned firms and entrepreneurship was seen as a risky career path. Alibaba, previously recognized as an on-line shopping company, also has investments in sports content, microchips and facial recognition technology and has been positioning itself as a serious player in cloud computing. Mr. Ma said in the letter, “The one thing I can promise everyone is this: Alibaba was never about Jack Ma, but Jack Ma will forever belong to Alibaba.”

1. What do we learn about Abibaba from this passage?

A．It was founded by Jack Ma alone.

B．It is nothing more than an on-line shopping company.

C．It was founded at the time when private-owned firms was in a minority.

D．Its shareholders meeting holds twice a year.

2. What can we infer from paragraph 2?

A．Hoogewerf speaks highly of Jack Ma’s firm.

B．Bill Gates and Jack Ma have a lot in common.

C．Other than stars and billionaires, Jack Ma makes few friends.

D．Jack Ma is an influential person to unite his friends.

3. Jack Ma will do the following things after stepping down except________.

A．Helping people in need.

B．Ensuring the company’s transition.

C．Education career.

D．Suggesting candidates for the board.

4. What’s the best title for this passage?

A．The Brief Introduction of Jack Ma

B．Daniel Zhang to Take Over Alibaba

C．Alibaba’s Development

D．Jack Ma to Step Down as Alibaba’s Head