Ants are troublesome, best known for itchy bites and ruining picnics. But, a new species of crazy ant is taking over Texas. In some ways they appear to be worse than fire ants and there's no good way to stop them* These ants move fast and are plentiful in some areas.

The crazy ants first sprang in Pearland in 2002 and have been becoming more and more of a problem ever since.“An invasion of these can be so extreme that it's hard to call it just a nuisance," University of Texas entomologist Edward LeBrun told The Austin American-tatesman. “The ants have been known to crawl into and ruin televisions, appliances and other electronic devices. No one is entirely sure why," He said.

David Oi , a research entomologist at the Department of Agriculture, told The New York Times in 2013, the strange idea that the ants are actually attracted to the electricity itself can't be ruled out.

The crazy ants or Raspberry ants-yep, that's actually what they are called-are found in 23 Texas counties. The ants have very little venom(毒液), but do cause a slight sting when they bite. Mostly, though, they're a hazard to electrical equipment.

They are a relatively new species in the region and little is known about how to control or kill the population. And, unfortunately, there doesn't seem to be much that can be done about them right now. So, for the moment, the best advice is not to stay close to ant piles and groups. and hope that none make it inside to crawl around the electronics.

1.What do the ants do in Texas?

A. Bite some people. B. Damage local crops.

C. Destroy appliances. D. Pollute environment.

2.The underlined word "nuisance" in Paragraph 2 is closest in meaning to " ”.

A. story B. problem

C. visit D. failure

3.When meeting with ant piles, we'd better .

A. kill them all B. control them

C. drive them away D. stay away from them

4.What can we know from the text ?

A. The crazy ants first. appeared in Texas in 2013.

B. The crazy ants cause huge loss to the people in Texas.

C. The government is taking measures to deal with the ant.

D. David Oi is sure why the ants ruin electronic devices.

It may seem like a moment in a science fiction movie. In a fierce battle, a creature loses an arm but, then, grows another one to take its place.

However, this is not science fiction. It is scientific fact. Some fish and amphibians, such as salamanders, can regrow lost limbs and organs.

As mammals evolved they lost the ability to regrow, or regenerate, parts of their body. However, experiments show that it may be possible to regain that ability.

Tropical freshwater zebrafish are popular pets. They are also popular as lab animals. Their embryos(胚胎) are clear, or translucent. They can regrow damaged fins, skin and hearts. Zebrafish are also genetically(基因地) similar to humans.

In 2013, the website Sci-News reported that researchers had found that 70 per cent of “protein-coding human genes” are related to genes found in the zebrafish. The report also said that researchers at the Wellcome Trust Sanger Institute in Britain also found that 84 per cent of genes known to be connected to human disease have a zebrafish counterpart.

Scientist Wang Yadong is one of the Pittsburg researchers. He and his team are studying the ability of zebrafish to regenerate limbs and organs. Wang says you can cut away about 20 per cent of the zebrafish heart and it will regenerate. He add that same process may be able to help humans.

Scientists injected(注射) an “extracellular matrix,” or ECM, from the heart of a zebrafish into a severely damaged mouse heart. They found that the heart muscle regrew in days. They found something else. The healing was even faster when the ECM was taken from zebrafish that was itself in the process of re-growing damaged tissue.

1.The main reason why the zebrafish were chosen as lab animals is that _____________ .

A. they are popular pets

B. their bodies are clear to study

C. they are genetically similar to humans

D. they are easy to find for the researchers

2.What does the underlined word “counterpart” in Paragraph 5 probably mean?

A. A similar thing.

B. A different fish.

C. A human being.

D. A little mouse.

3.After injecting ECM from a zebrafish into the damaged mouse heart, what did scientists find?

A. The zebrafish died quickly.

B. The mouse heart regrew in days.

C. The zebrafish heart regrew quickly.

D. The mouse healed more slowly than normal.

4.Where is the most probably taken from?

A. A science fiction.

B. A guide book.

C. A fashion magazine.

D. A science report.

If you have a cat, you already know that a cat isn’t a dog that doesn’t have to be walked. If you’re about to bring a cat into your family, you need to understand that basic fact. The common wisdom is that dogs are friendlier than casts.

In recent years, scientists who have done DNA studies have offered a better way to understand cats. Unlike other animals that people feed, cats domesticated themselves, and, in a way, trained humans. Cats decided to live close to humans because doing so benefited the casts themselves.

Studies show that cats have lived with humans for about 12,000 years, since people first settled down and started farming. When people started storing grain, mice arrived and started eating the grain. Clever cats figured out that mice settlements where people stored grain were easy for hunting, so they started hanging around. Cats did what they needed to do to get the people to let them stay, but they kept up their independence. Over time, cats allowed humans to get a bit closer to them. Later, the farmers did befriend the cats. Certainly, it didn’t do them any harm because they could see the cats were really helping them out by eating mice.

Today, about a third of American families have cats. In most of those homes, the cats are still more interested in pleasing themselves than in pleasing their human families. A dog may do anything it can to make you happy, but kitty will teach you to make kitty happy.

1.Compared with dogs, cats are______.

A. colder B. friendlier

C. more warm-hearted D. more frightening

2.According to the text, why do cats decide to stay close to humans?

A. To be useful to themselves B. To protect grain from mice

C. To rely on humans for food D. To keep up their independence

3.What may be the best title for the text?

A. A common point between dogs and cats

B. The reasons why people like dogs

C. A disadvantage of raising cats

D. The basic fact about cats.

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