题目内容

【题目】After losing contact for twenty years, they met again _________ in a party.

A.by mistake B.by coincidence

C.on purpose D.on display

【答案】B

【解析】

试题分析:考查介词词组辨析。A.by mistake错误地 B.by coincidence偶然地,碰巧C.on purpose故意地D.on display公开展出;句意:在失联了二十年后,他们偶然地又一次在派对上碰到。根据句意,故选B.

练习册系列答案
相关题目

【题目】【原创】Humans are well-equipped for life on Earth. But in space, it is different. Low or zero gravity changes how the blood flows and causes motion sickness, muscle loss and tiredness. Weightlessness can also cause bone loss. But scientists are experimenting with little worms to better understand how space travel affects astronauts.

The millimeter-long worm is called C. elegans. The see-through worm is often used in medical studies because its life is only about two weeks long. Seventy percent of its DNA is the same as human DNA.

Sabanayagam is a scientist, who built a micro-gravity simulator to test how C. elegans would perform in the actual zero gravity of space.

Scientists put the worms into the simiulator full of water. After a week they take out the worms. They look for changes in the worms' epigenome,which are chemical markers that tell the DNA in the cells how to perform. The epigenome can be changed by the environment. And those changes pass from one generation of worms to the next.

"When the worms are in a liquid environment, some epigenomic marks remain even when we take the animal out of the liquid environment and put it back into normal ground conditions. So its offspring keeps this epigenomic memory of the parents' liquid environment or microgravity environment."

The information the scientists have gathered suggests that the epigenomic marks appear during the early part of a worm’s life.

Mr. Sabanayagam says he thinks scientists can find genes in the human similar to those in the worms that responded to microgravity and scientists could possibly observe those genes closely when astronauts travel in space.

Sabanayagam expects C. elegans to visit the International Space Station within two years. He says he hopes information gathered from the worm studies can be used to develop simple, low-cost and quick tests to measure an astronaut's health.

【1】What does the underlined word zero gravity” mean?

A. Seasickness B. Muscle loss

C. Weightlessness D. Tiredness.

【2】 From the passage we can know C. elegans _____.

A. has exactly the same DNA as human

B. is harmful to human

C. is often used in agricultural research

D. has a short life period

【3】Why do scientists experiment with C. elegans?

A. Because it has strong life power in water.

B. Because they want to find how space travel affects astronauts

C. Because the worm will be taken into space.

D. Because they want to find what its DNA like.

【4】What is Sabanayagam’s attitude toward the result of the experiment?

A. Hopeful and satisfied.

B. Doubtful and unsure.

C. Sad and disappointed.

D. Surprised and unbelievable.

【5】Which section of a newspaper can you find the passage?

A. Education. B. Science.

C. Advertisement. D. Entertainment.

违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com

精英家教网