题目内容
In order to protect valuable energy, snails(蜗牛) basically play a game of follow-the-leader, a new study finds. Snails create trails of mucus(黏液) to help them move smoothly across the ground, mainly in search of food or a partner, but making all that mucus uses up a lot of energy.
“Snails use a lot of energy, probably a third, creating mucus,” said Mark Davies of the University of Sunderland, lead author of the study published in the journal Proceedings of the Royal Society. “This process is very tiring indeed— much more so than walking, swimming or flying.”
Davies and his workmates studied marine snails off the coast of Britain and discovered that to save some of this important energy, the snails sometimes follow the existing mucus trails laid down by other snails to get around and so only have to create a small part of the mucus needed to make a new trail.
“The fact that they can make savings has an effect on as much as they have to save more energy to do other things like reproducing,” Davies said.
The energy saving may also help snails which live in environments where food is not enough, making the energy harder to replace.
Biologists had long guessed that snails behaved this way, but this is the first study to directly observe it. Davies said that it is likely that all snails use this means of cutting energy as they work hard through life.
45. What’s the function of mucus that snails create?
A. To find their food B. To find their way back
C. To save their energy D. To help them move smoothly
46. According to the passage, which of the following statements is TRUE?
A. The snail’s life is very hard.
B. The snails don’t need much to reproduce.
C. This is the first time to do the guess.
D. The snails will replace more energy in places lacking food.
47. From the passage we know that ______.
A. snails’ trails are sometimes reused
B. snails’ food is difficult to find
C. snails can live a long life
D. only marine snails have the ability
48. What does the passage mainly talk about?
A. How snails move and work.
B. Snails save energy by reusing mucus trails.
C. A new study finds the mysteries of snails.
D. Snails make full use of their energy.
45—48 DAAB
B
It is the duty of every man to work. The life of a lazy man is of no use to himself and to others. The man who is too lazy to work is the man who is generally most ready to beg or to steal. Every boy, when he is young, should learn how to do some useful work.
But it is not enough that a boy should learn some kind of work. He should put his heart and soul completely into his work, and not waste his spare time. “Work while you work and play while you play” is as good a rule for young people as for the old!
There is no better help to diligence (勤奋) than the habit of early rising, and this, just like all other good habits, is most easily formed in youth. There is an English saying, “Lost time never returns”. This means that everybody must be diligent and make good use of his time. One must study hard when one is young so that one may make great progress, succeed in life and become useful to one’s country. Those who are diligent will never become beggars. Therefore, we can say that diligence is the mother of success.
【小题1】From the passage, we know that those who are too lazy to work will_________.
A.waste their time |
B.help others |
C.become beggars or thieves |
D.make progress some day |
A.form the good habit of getting up early in youth |
B.learn about some good habits |
C.work while they work and play while they play |
D.work all the time without playing |
A.is diligent in his study |
B.loves life |
C.spends some time learning something |
D.makes up for his lost time |
Our world natural park is one of the most famous parks in the world. Millions of visitors from different countries visit this park every year. In order to protect it,please do as follows:
◆Protect the natural and cultural heritage. Don’t damage or deface any buildings,dis-plays and other facilities. Take care of all plants. Put rubbish in the bins provided.
◆Take care when you are going up and down steps or stairs and when you are walking nearby the waters.
◆Please buy tickets before entering the scenic spot. One ticket is only for one person. A-dult:$60 per ticket. Children over 6 and under 18,half price. People over 60 and children un-der 6 are free.
◆If you are going into the wooded and hilly lands,for your own safety,please go with three people at least and don't take any tinder(易燃物)along with you. The hill is steep, so please take care of yourself.
◆This scenic spot is the reserve of water source: No fishing,swimming,washing and any behaviors that are harmful to the water source. Meanwhile,please follow the management rules of the scenic spot conscientiously.
◆Opening time:From Monday to Friday,8:00 a. m.~18:00 p. m.;From Saturday to Sunday,6:00 a. m:一24:00 p. m.
◆Small animals such as rabbits,peacocks,squirrels,frogs must be taken care of: None of them shall be killed.
If you have any trouble in visiting our world natural park,please call 477一866一7044.Our staff will do our best to help you.
【小题1】How much will be paid for a 65-year-old man with his 8-year-old grandson?
A.Free. | B.$30. | C.$60. | D.$120. |
A.4 | B.6 | C.8 | D.10 |
A.clean | B.polluted | C.dangerous | D.colorful |
A.Tourists can hike alone in the hilly lands. |
B.Small animals are under protection in the park. |
C.Children can play with small animals. |
D.Tourists can have a swim in the water. |