【推荐2】The number of insects in the world has fallen by 45 percent in the past 35 years. Scientists say this could be dangerous for humans. A report on insect numbers has been published in the journal “Science”. It says the human population has doubled since 1980 while the number of insects has nearly halved. One of the biggest reasons for this loss of insects is the act of cutting down trees or burning them. Many of the places where insects live are disappearing because of new cities and land being used for farming. Another reason is global warming. Scientists say that in the UK, the number of butterflies, bees and wasps(黄蜂) has fallen by up to 60 percent. Many countries are worried about the disappearance of them.

Scientists say the decline in insect populations will lead to many problems for humans. One of the biggest dangers is that there will be fewer insects to pollinate flowers. This means that farmers will have problems growing food. The lead author of the report, Professor Rodolfo Dirzo, said falling numbers of insects could also lead to more diseases in humans. He said rats and mice would have less food to eat so they will move to cities and bring diseases with them. Dr. Ben from London University said we needed to stop more insects from dying. He added that scientists must understand what species(物种) are winning and losing in the fight for survival. He said this knowledge would help us to protect the “helpful” insects.

1. According to the passage, which of the following statements is TRUE?

A．The number of insects has fallen by 35 percent in the past 45 years.

B．The human population on the earth has nearly halved since 1980.

C．The number of insects has been twice as large as that in 1980.

D．Bee and butterfly numbers have fallen by 60 percent in the UK.

2. Which of the following is NOT the reason for insect disappearance?

A．Global warming.	B．Terrible weather.
C．Appearance of new cities.	D．Loss of trees.

3. What does the underlined word “pollinate” mean in the second paragraph?

A．播种	B．采摘
C．授粉	D．捕食

4. What can be inferred from the passage?

A．More diseases will be brought to cities by rats and mice.

B．Dr. Ben reminded us to prevent more insects from dying.

C．Research on the survival of insects may be helpful to humans.

D．In the future, it isn’t important for farmers to grow food without insects.

【推荐3】A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.

Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.

Now the same oxygen sensors found in frog skins and in the lungs of mammals (哺乳动物) have unexpectedly been discovered in the skin of mice.

“No one had ever looked,” explained Randall Johnson, a biologist researcher.

Mice and frogs are quite distant relatives, so the fact they have these molecules (分子) in common in their skin suggests they might well be found in the skin of other mammals, such as humans.

“We have no reason to think that they are not in the skin of people too,” Johnson said.

These molecules not only detect oxygen, but help increase levels of vital red blood cells, which carry oxygen around the body. Normal mice breathing in air that is 10 percent oxygen-a dangerously low level similar to conditions at the top of Mount Everest, and about half that of air at sea level. However, mice that had the oxygen sensor HIF-1a genetically removed from their skin failed to produce this hormone (荷尔蒙) even after hours of such low oxygen.

These findings, if they hold true in humans, suggest one could raise the level of oxygen circulating inside the body. This could help treat lung diseases and disorders such as anemia (贫血症) without injecting drugs, which make up a multibillion-dollar market, Johnson said.

Athletes also often try to get more oxygen delivered to their muscles in order to improve their performance. They often do this by training at high altitudes or in low-oxygen tents. The new study suggests they might want to expose their skin as well as breathing in low-oxygen air to improve their performance. “It’s hard to say what exactly might be done, however — there’s a lot we don’t know yet,” Johnson explained.

The scientists detailed their findings in the April 18 issue of the journal Cell.

1. Which of the following statements is TRUE according to the passage?

A．Johnson believes that Oxygen sensors also exist in human skin.

B．People have to surf the Internet to read detailed findings.

C．It has been proved that these findings help treat lung diseases.

D．It has long been expected oxygen sensors exist in mice’s skin.

2. One of the functions of the molecules mentioned above is _______.

A．carrying oxygen around the body

B．improving athletes’ performance

C．detecting oxygen

D．increasing level of oxygen

3. What is Johnson’s attitude to the application of the findings to the athletes’ training?

A．Negative.

B．Doubting.

C．Positive.

D．Hesitating.

4. The best title of the passage may be _______.

A．Great Findings Benefits Athletes A Lot

B．Frogs And Mice Are Distant Relatives

C．First Known Animal Breathes Through Skin

D．Humans Might Sense Oxygen Through Skin