题目内容

They've kept up a friendship with the teacher whom they were at school _____ twenty years ago.


  1. A.
    with
  2. B.
    about
  3. C.
    since
  4. D.
    till
A
易错选B或C, whom在这里指代the teacher,因此定语从句可还原为: They were at school/with the teacher twenty years ago.
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阅读下列短文,从每题所给的四个选项中选出最佳选项。

  We know, painkillers in a tablet can make your headache go away, and antibiotic from a tube can prevent your cuts from becoming infected.Can medicine come in chicken eggs? A team of scientists from Scotland says “yes.” They've kept some special chickens that lay eggs with disease-treating drugs inside.

  These drugs are made of molecules called proteins.Animals make thousands of proteins-they're the main ingredients(成分)in skin, hair, milk, and meat.Since animals can make proteins easily, they're good animals for making protein drugs.

  Researchers have already made cows, sheep, and goats that pump out protein drugs in their milk.But chickens are cheaper to take care of, need less room, and grow faster than these other animals.“Those qualities could make chickens a better choice to become living drug factories.” says Simon Lillico of the Roslin Institute near Edinburgh, Scotland.

  Lillico and a team of researchers changed chickens' DNA-the code that tells cells how to make proteins-so that the birds' cells made two protein drugs.One drug can treat skin cancer, and the other treats a nerve disease called multiple sclerosis.

  The scientists changed the chickens' DNA so that the birds made these drugs only in their egg whites.This protects the chickens' bodies from the drugs' possible harmful effects and makes it easy for scientists to collect the drugs.

  These special chickens can pass on their drug-laying abilities to their chicks.So far, the Scottish researchers have kept five generations of drug-producing chickens.But the scientists need to improve these chickens.The chickens don't make enough drugs to treat people yet.Once the researchers perfect their technique, you might eventually take your medicine from chicken eggs.

(1)

What is the best title of the passage?

[  ]

A.

Animals and Protein Drugs.

B.

Medicine Packaged in Various Forms.

C.

A Scotland Scientist and His Chickens.

D.

Chickens:a Better Choice of Living Drug Factories.

(2)

Which of the following is Not True according to the passage?

[  ]

A.

It takes much shorter time for chickens to grow than cows, sheep and goats.

B.

Compared to cows, sheep and goats, chickens are less expensive to be raised.

C.

Chickens can produce the best quality of drugs among the drug-producing animals.

D.

Chickens are smaller in size than cows, sheep and goats and therefore need less room.

(3)

Why did the chickens make the drugs only in the egg whites?

[  ]

A.

Because it will help to collect the drugs easily.

B.

Because it will not change the DNA of the chickens.

C.

Because it will be easy for the patients to take the drugs.

D.

Because it will prevent possible harmful effects on the patients.

(4)

What can be inferred from the passage?

[  ]

A.

Scottish researchers have kept five more drug-producing chickens.

B.

This technique still needs improving so as to satisfy the normal application.

C.

In the future people with diseases will take eggs instead of pills.

D.

The chicks need to be improved so as to carry the same ability as their parents.

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