2 . Combining knowledge of chemistry, physics, biology, and engineering, scientists from McGill. University develop a biomaterial tough enough to repair the heart, muscles, and voeal cords. representing a major advance in medicine.

“People recovering from heart damage often face a long and tricky journey. Healing is challenging because of the constant movement tissues must withstand (承受) as the heart beats. The same is true for vocal cords. Until now there was no injectable (可注射的) material strong enough for the job,” says Guangyu Bao, a PhD candidate in the Department of Mechanical Engineering at McGill University.

The team, led by Professor Luc Mongeau and Assistant Professor Jianyu Li, developed a new injectable hydrogel (水凝胶) for wound repair, which is a type of biomaterial that provides room for cells to live and grow. Once injected into the body, the biomaterial forms a stable structure allowing live cells to grow or pass through to repair the injured organs.

“The results are promising, and we hope that one day the new hydrogel will be used to restore the voice of people with damaged vocal cords,” says Guangyu Bao.

The scientists tested the durability of their hydrogel in a machine they developed to copy the extreme biomechanics of human vocal cords. Vibrating (振动) at 120 times a second for over 6 million cycles, the new biomaterial remained undamaged while other standard hydrogels broken into pieces, unable to deal with the stress of the load.

“We were incredibly excited to see it worked perfectly in our test. Before our work, no injectable hydrogels possessed both high porosity (多孔性，疏松) and toughness at the same time. To solve this issue, we introduced a pore-forming polymer to our formula（配方),” says Guangyu Bao.

The innovation opens new ways of making progress for other applications like tissue engineering. The team is also looking to use the hydrogel technology to create lungs to test COVID-19 drugs.

1. What did the researchers develop the new biomaterial for?

A．To experience a tricky journey.	B．To substitute damaged organs.
C．To advance the progress of medicine.	D．To repair the injured organs.

2. What is special about the biomaterial compared to other materials?

A．It is heavier but advanced.	B．It is injectable and strong.
C．It is more expensive.	D．It is easier to break.

3. What might the researchers do about the biomaterial?

A．Use it to cure COVID-19.	B．Increase its toughness for repairing lungs.
C．Invent artificial organs for drug test.	D．Improve its formula further.

4. What does the author intend to do by writing this passage?

A．To introduce a newly-developed material.	B．To stress the importance of innovation.
C．To promote the sales of a new hydrogel.	D．To show his respect to the researchers.

4 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Bioprinting is medically and bio — technologically similar to 3D printing. By using the same principles, the aim is to     1     (rapid) develop living structures similar to human-grown organs and tissue that can be used to treat people or test new drugs. Bioprinting may be a relatively new field but the results so far are     2     (encourage).

Australian researchers have used neural cells in a custom-made bioink to create a “desktop brain”     3     allows doctors to test brain function, new drugs and study brain disorders. Meanwhile, medicine scientists in the US have created a bioprinter able     4    (construct) ear, muscle and bone structures with the right size,     5    (strong) as well as function for implantation.

One of the primary goals of bioprinting is to create functioning organs, for example, hearts. By printing compatible(兼容的) organs using a patient's own cells, the donor     6    (wait) list could become a thing of the past. To get     7     this point there have been some important breakthroughs in printing vascularized (血管化的) tissue in complex 3D shapes.

Organ printing can improve     8     health of society in general by wiping off the problem of diseases     9     (cause) by organ failure, costly treatments and social care. That promise may be years away from realization but rapid typing enabled by bioprinting at present     10    (push) medical advances forward at pace.

5 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Increasingly, Americans are becoming their own doctors by going to diagnose their symptoms, order home health tests or medical devices, or even self-treat their illnesses with drugs from Internet pharmacies(药店).Some avoid doctors because of the high cost of medical care, especially    1     they lack health insurance. Or they may stay away because they find it    2    (embarrass) to discuss their weight, smoking, alcohol consumption or couch potato habits. Patients may also fear what they might learn about their health, or they distrust physicians because of negative     3     (experience) in the past. But    4    (play) doctor can also be a deadly game.

Every day, more than six million Americans turn to the Internet    5    medical answers--- and most of them aren’t nearly sceptical enough of what they find. A 2002 survey by the Pew Internet &American Life Project found that 72 percent of those    6    (survey) believe all or most of what they read on health websites. They shouldn’t look up “headache” and the chances of finding     7    (rely) and complete information, free from a motivation for commercial gain,    8     (be) only one in ten, reports an April 2005 Brown Medical School study. Of the 169 websites the researchers rated, only 16 scored as “high quality”. Recent studies found faulty facts about all sorts of other disorders, causing one research team to warn that a large amount of incomplete, inaccurate and even dangerous    9     (inform) exists on the Internet.

The problem is most people don’t know the safe way to surf the Web. “They use a search engine like Google, get 18 trillion choices and start clicking. But that’s risky, because almost anybody can put up a site that looks authoritative ( 权威的)，so it’s hard to know if what you’re reading is     10    (reason) or not,” says Dr.Sarah Bass from the National Cancer Institute.