Ants have a reputation for strength,organization and teamwork.But researchers have now discovered that a key secret to the success of ants is their ability to identify the importance of age in the work place.

A study of Gentral American leaf-cutter ants has shown that the younger and stronger members are give the toughest job of cutting therough the leaves they harvest.Their sharp youn teeth do this job effectively,but as they get older their teeth become relatively worn and blunt.

But rather than being retired or abandoned by the group,the ageing ants are given a new role more suyted to their physical abilities.They become carriers and teansport the leaves back to the kingdom where they are harvested for food.

The findings by researchers from the University of Oregon and the Oregong State University support previous research showin the survival of a leaf-cutter kingdom depends on the efficiency(效率）of is workers.

“Cuting leaves is hard work,”said Dr.Robert Schofield,who led the research team.“Much of the cutting is done with a V-shaped blade(刀片）between teeth on their jaws.This blade starts out as sharp as the sharpest razor blade that humans have developed.”But over rime the teeth become blunter and the cutting job slows down.The team estimated that,because of this age-related wear,a colony(蚁群)spent twice the energy cutting leaves than it would if all the ants had sharp blades.Its findings support the idea that wear and break can be significant problems for insects as well as largre animals.

Like humans,leaf-cuttre ant recognize that older members of the group can still make a worhwhile contribution to society.“This study shows an advantage of social living that we are familiar with,”said Dr.Schofield.

1.The younger and stronger ants do the toughest job because      .

2.The undrelined word“blunt”in the second paragraph can be replaced by      .

3.What happens to the ants when they become old?

4.It can be learned from the passage that       .

5.What can be the best title for the passage?

After John’s first wife died, he gets married again. His second wife was more younger than he was and they often quarreled. John once came home lately after work, his wife said to him that he had waited for two hours. She was too angry that she gave him a push, which made him fall down the stairs so he is old and weak. When Steven, one of John’s neighbor, heard the noise, he was eager to know which was happening. He came John’s front door and knocked. “What’s happened?” he asked. “My coat fell down the stairs,” John answered. When the neighbor said a coat wouldn’t make so many noise, John answered, “Of course it would if I was inside it!”

Ants have a reputation for strength,organization and teamwork.But researchers have now discovered that a key secret to the success of ants is their ability to identify the importance of age in the work place.
A study of Gentral American leaf-cutter ants has shown that the younger and stronger members are give the toughest job of cutting therough the leaves they harvest.Their sharp youn teeth do this job effectively,but as they get older their teeth become relatively worn and blunt.
But rather than being retired or abandoned by the group,the ageing ants are given a new role more suyted to their physical abilities.They become carriers and teansport the leaves back to the kingdom where they are harvested for food.
The findings by researchers from the University of Oregon and the Oregong State University support previous research showin the survival of a leaf-cutter kingdom depends on the efficiency(效率）of is workers.
“Cuting leaves is hard work,”said Dr.Robert Schofield,who led the research team.“Much of the cutting is done with a V-shaped blade(刀片）between teeth on their jaws.This blade starts out as sharp as the sharpest razor blade that humans have developed.”But over rime the teeth become blunter and the cutting job slows down.The team estimated that,because of this age-related wear,a colony(蚁群)spent twice the energy cutting leaves than it would if all the ants had sharp blades.Its findings support the idea that wear and break can be significant problems for insects as well as largre animals.
Like humans,leaf-cuttre ant recognize that older members of the group can still make a worhwhile contribution to society.“This study shows an advantage of social living that we are familiar with,”said Dr.Schofield.
【小题1】The younger and stronger ants do the toughest job because      .

Your genetic makeup plays a big part in determining your size and weight. If both your parents are tall, there is a good chance you’ll be tall. But if your parents are smaller than average, you may want to rethink that professional basketball career!

   The same goes for your body type. Have you ever heard someone say a person is “big boned?” It’s a way of saying the person has a large frame, or skeleton(骨骼). Big bones usually weigh more than small bones. That’s why it’s possible for two kids with the same height, but different weight, to both the right weight.

   Being overweight can run in someone’s family, but it may not be because of their genes. Poor eating and exercise habits also run in families and these may be the reasons the members of a family are overweight. And even though some kids gain weight more easily than others, when they eat right and exercise, most kids can have a healthy weight that’s right for them. It’s true- the way you live can change the way you look.

   How much your weight is a balance between the calories you eat and the calories you use. If you eat more calories than your body needs to use, you will gain too much weight. If you spend you free time watching TV, your body won’t use as many calories as it would if you played basketball, skated, or went for a walk. But if you eat more and exercise less, you may become overweight. On the other hand, if you eat less and exercise more, you may lose weight.

1. Which one can be used as the best title of this passage?

A. What Makes Me the Weight I Have?

B. How Can I Lose More Weight?

C. What Makes Me the Height I Have?

D. Is the Way You Live Important?

2._______ might be the most important in determining your size and weight.

A. Your father and mother

B. Your genetic structure

C. Your diet and habit

D. Doing exercise in the morning

3.If two kids are of the same height _______.

A. they must have large frames.

B. they must be of the same size

C. they must be of the same weight

D. their weight might be different

4.Which one of the following is TRUE according to the third paragraph?

A. Eating right and exercise normally can keep you healthy.

B .The members of a rich family must be overweight.

C. The way you live has nothing to do with the way you look.

D. the members of a poor family can’t be overweight.

5. ______ can help you to get your weight right.

A. Watching TV in your spare time.

B. Eating more and doing less exercise

C. Eating less and doing more exercises

D. Sleeping more in your spare time

Your genetic makeup plays a big part in determining your size and weight. If both your parents are tall, there is a good chance you’ll be tall. But if your parents are smaller than average, you may want to rethink that professional basketball career!

   The same goes for your body type. Have you ever heard someone say a person is “big boned?” It’s a way of saying the person has a large frame, or skeleton(骨骼). Big bones usually weigh more than small bones. That’s why it’s possible for two kids with the same height, but different weight, to both the right weight.

   Being overweight can run in someone’s family, but it may not be because of their genes. Poor eating and exercise habits also run in families and these may be the reasons the members of a family are overweight. And even though some kids gain weight more easily than others, when they eat right and exercise, most kids can have a healthy weight that’s right for them. It’s true- the way you live can change the way you look.

   How much your weight is a balance between the calories you eat and the calories you use. If you eat more calories than your body needs to use, you will gain too much weight. If you spend you free time watching TV, your body won’t use as many calories as it would if you played basketball, skated, or went for a walk. But if you eat more and exercise less, you may become overweight. On the other hand, if you eat less and exercise more, you may lose weight.

Which one can be used as the best title of this passage?

A. What Makes Me the Weight I Have?

B. How Can I Lose More Weight?

C. What Makes Me the Height I Have?

D. Is the Way You Live Important?

_______ might be the most important in determining your size and weight.

A. Your father and mother

B. Your genetic structure

C. Your diet and habit

D. Doing exercise in the morning

If two kids are of the same height _______.

A. they must have large frames.

B. they must be of the same size

C. they must be of the same weight

D. their weight might be different

Which one of the following is TRUE according to the third paragraph?

A. Eating right and exercise normally can keep you healthy.

B .The members of a rich family must be overweight.

C. The way you live has nothing to do with the way you look.

D. the members of a poor family can’t be overweight.

______ can help you to get your weight right.

A. Watching TV in your spare time.

B. Eating more and doing less exercise

C. Eating less and doing more exercises

D. Sleeping more in your spare time