![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
With a great weight() my mind,I turned into a by-stander.
A.to take off
B.taking off
C.taken off
D.being taken off
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
A.to take off
B.taking off
C.taken off
D.being taken off
A.give way
B.give up
C.give in
D.give back
The toothless, or baleen, whales belong to the suborder of Mysticeti. This is a group of generally large whales, formerly abundant in all the oceans of the world. Though reduced by hunting, most species are still found along the coasts of the United Stated and Canada. All but two of the Mysticeti reach 40 feet or more at maturity, with the blue whale running up to 100 feet and tipping the scales at up to 130 tons. This whale is by far the largest creature that has ever lived on earth, 4 times the weight of the largest dinosaur, 30 times that of an elephant.
With what topic is the passage mainly concerned?
A.Breeding habits of whales.
B.Differences between whales.
C.Efforts to preserve whales.
D.The intelligence of whales.
Suppose a man wanted to reach a distant star. Even if he traveled his whole life, he would have to move faster than the speed of the light. Nothing can move that fast except light itself.
Strange things happen to an object when it moves rapidly. The object weighs more. An object moving at 86 percent of the speed of light is twice as heavy as it is at rest. A stick appears shorter. A clock runs more slowly. A man would not age so fast as he would on the earth.
Light travels more than 186,000 miles a second, or about 11 million miles a minute. In one year, light travels six trillion miles. That great distance is called a light-year. It is used to measure distance in space.
The star closest to our sun is Alpha Centauri. It is more than four light-years away. If one traveled at the speed of light, he could make a round trip to Alpha Centauri in nine years. But, even at that speed, he could not reach Alcaid (北斗星) in the handle of the Big Dipper. A one-way journey to Alcaid would take almost 200 years
1.In this passage the words “closest to our sun” means the star().
A、the earth we live on
B、Alpha Centauri
C、the Big Dipper
D、the moon
2.A one-way journey to Alcaid would take().
A、about nine years
B、less than four years
C、almost 200 years
D、less than 100 years
3.Why do we measure the distance in light-years instead of miles?()
A、Units of light-years sound better.
B、Using light- years reduced the number of figures used.
C、We used to measure distance in light-years long ago.
D、We do not make mistakes when we use light-years.
4.If a stone moved at the speed of light, it().
A、would weigh twice more than it is motionless
B、would weigh as much as it is on earth
C、would weigh less than it is on earth
D、would not have weight at all
5.This story is mainly about ().
A、the distance between the sun and the other stars
B、the problems of traveling to faraway stars
C、what happens when we travel faster than the speed of light
D、the tool we use when we go to faraway stars
Another advantage of money is that it is a measure of value, that is, it serves as a unit in terms of which the relative values of different products can be expressed. In a barter economy it would be necessary to determine how many plates were worth one hundred weight of cotton, or how many pens should be exchanged for a ton of coal, which would be a difficult and time-consuming task. The process of establishing relative values would have to be undertaken for every act of exchange, according to what products were being offered against one another, and according to the two parties'desires and preferences. If I am trying to barter fish bananas, for example, a lot would depend on whether the person willing to barter fish for bananas, for example, a lot would depend on whether the person willing to exchange bananas is or not keen on fish.
Thirdly, money acts as a store of wealth. It is difficult to imagine saving under a barter system. No one engaged on only one stage in the manufacture of a person could save part of his output, since he would be producing nothing complete. Even when a person actually produced a complete product the difficulties would be overwhelming. Most products deteriorate fairly rapidly, either physically or in value, as a result of long storage; even if storage were possible, the practice of storing products for years on would involve obvious disadvantages-imagine a coal-miner attempting to save enough coal, which of course is his product, to keep him for life. If wealth could not be saved, or only with great difficulty, future needs could not be provided for, or capital accumulated to raise productivity.
Using money as a medium of exchange means that______.
A.you have to sell something in order to buy something
B.you have to buy something in order to sell something
C.you don't have to buy something in order to sell something
D.the seller and the purchaser are the same person
Exercise helps you________.
A.save calories and gain weight
B.save calories but lose weight
C.bum calories and lose weight
D.burn calories but gain weight
Will this light shelf__________the weight of all these books?
A.include
B.maintain
C.contain
D.sustain
A.change
B.in
C.with
D.convert
A.counter weight
B.crankshaft
C.flywheel
D.ring gear
Doctor: Have you lost weight recently, Mr. Bush? Bush: No, doctor. Actually, ______.
A.I've become three pounds fatter
B.I've got three pounds weight
C.I've added to three pounds
D.I've put on three pounds