27． Scientists ____to make the deserts into good land again．A． carry water'B．grow foodC． do nothingD． study a lot
27． Scientists ____to make the deserts into good land again．
A． carry water'
B．grow food
C． do nothing
D． study a lot
相关考题：
27． From the passage we know that fresh water doesn't come from________ ．A．riversB．lakesC．undergroundD．the sea
At the edge of the land lies the ocean, ____ the earth is covered with water. A.whichB.thatC.whereD.when
A:It's a good ideA.But who's going to _______ the plan? B: I think Tom and Greg will. A.set asideB. carry outC. carry awayD. get through
27． According to(根据) the passage, a good breakfast means _______．A． meat and fishB． eggs and riceC． a lot of foodD． the right food
AWhy do plants grow in some places and not in others? Why does some land have so much growing on it，while other land has almost no plants growing on it at all?To grow plants need several things． One is warmth． In very cold places almost nothing grows． Plants also need water． In very dry parts of the earth only a few unusual plants can grow． That's why dry deserts everywhere are almost not covered by trees or grass．Plants must also have a place in which to f，ut down their roots and grow． They find it diffi-culr to grow on hard land． The town is built on hard land． The plants here have only the soil found between the cracks of the stones Io grow in．Another thing plants must have before they can grow is food．Whar will happen if we try to make things grow on the sandy beach? A few plants，such as beach grass，will grow in sand，L ut most plants won-t． Even if the weather is warm enough．and we water the plants each day． Many of them will die because the sand on this beach has al-most no food for plants．( )21． According to the passage，plants need _________ things to grow well．A． twoB． threeC． fourD． five
BScientists are trying to make the deserts into good land again． They want to，bring water to the deserts． But more and more places of the earth is becoming deserts all the time， Scientists may not be able to change the deserts． Scientists think that people make deserts． People are do-ing bad things to the earth．Some places on the earth don-t get very much rain． But they still don-t become deserts．This is because some green plants are growing there． Small green plants and grass are very helpful to dry places． Plants don't let the wind blow the earth away． When 8 little bit of rain falls，the plants hold the water． Without plants，the land can become a desert much more easily．( )26． Why can the land become a desert?A． Because some places don't get very much rain．B． Because plants don-t let the hot sun make the earth even drier．C． Because people don't keep the earth well．D． Because scientists haven-t learnt enough about the deserts．
28． Which is NOT true?A． The land never stops becoming deserts．B． Scientists ask the people to live in the deserts and grow food there．C． People do bad things to the earth．D． Scientists may not be able to change the deserts．
27． Why does eating apples make one-s stomach want less food?A． Because apples are delicious．B． Because apples are full of fiber and water．C． Because apples are sour．D． Because only apples are filled with calories．
The abbreviation L.W.R.P. on the navigation maps means ______.A.low water reference planeB.low winter runoff pointC.least water river planeD.land wall reference point
Good anchorage may be obtained anywhere in this water area, the bottom being generally mud and sand, vessel may have ______.A.good getting groundB.good holding groundC.good grabbing groundD.good handling ground
Good anchorage may be obtained anywhere，generally mud and sand，in this water area Vessel may have______．A.good dragging groundB.good towing groundC.good holding groundD.good grabbing ground
To the scientists' delight, their efforts have increased people's _______of the importance of saving water.A．awarenessB．commitmentC．agreementD．response
Some of our clients have complained that the time it takes to get a__________ from a service representative is enough to make them not want to use our services again.A. response B. respondingC. responded D. respond
What is the situation about the desertification in Africa?A.The deserts are replaced with grasslandsB.The deserts are expandingC.the deserts are moving northwardsD.the deserts are being deserted
共用题干第一篇Water Resources on the EarthThe second most important constituent（构成成分）of the biosphere（生物圈）is liquid water. This can only exist in a very narrow range of temperatures,since water freezes at 0℃and boils a 100℃．Life as we know it would only be possible on the surface of a planet which had temperature: somewhere within this narrow range.The earth's supply of water probably remains fairly constant in quantity.The total quantity of water is not known very accurately,but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers.Most of it is in the form of the salt water of the oceans一about 97 percent. The rest is fresh.But three-quarters of this is in the form of ice at the poles and or mountains and cannot be used by living systems until melted.Of the remaining fraction,which h somewhat less than one percent of the whole.There is 10—20 times as much stored underground water as there is actually on the surface.There is also a tiny,but extremely important fraction of the water supply which is present as water vapour in the atmosphere.Water vapour in the atmosphere is the channel through which the whole water circulation（循环） of the biosphere has to pass.Water evaporated（蒸发）from the surface of the oceans,from lakes and rivers and from moist（潮湿的）earth is added to it. From it the water comes out again as rain or snow,falling on either the sea or the land. There is,as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land,but there is more rainfall over the land than over the oceans and the balance is restored by the run off from the land in the form of rivers.There is more of rainfall________.A:over the mountains than over the riversB:over the rivers than over the mountainsC:over the land than over the oceansD:over the oceans than over the land
Rubbish can be thrown into the water （）.A、in a harbourB、in any placeC、25 miles off the landD、10 miles off the land
问答题Pollution is a problem because man, in an increasingly populated and industrialized world, is upsetting the environment in which he lives. Many scientists maintain that one of man’s greatest errors has been to equate growth with advancement. Now “growth” industries are being looked on with suspicion in case their side effects damage the environment and disrupt the relationship of different forms of life, the growing population makes increasing demands on the world’s fixed supply of air, water and land.
单选题What describes a flood current（）.AHorizontal movement of the water toward the land after high tideBHorizontal movement of the water toward the land after low tideCHorizontal movement of the water away from the land following high tideDHorizontal movement of the water away from the land following low tide
单选题If separating effect is not good, which measure should be taken （）Aworking at intervals and properly heatingBwarming up to 70℃, increase water supply flowCimproving impulse of water supplyDreducing water supply flow
单选题Which of the following statements concerning the water tube and fire tube boilers is not true?（）Anatural circulation of the water in the water tube boiler is better than that in the fire tube boilerBfor the same output the water tube boiler will carry less mass of water compared with the fire tube boilerCthe water tube boiler will cost shorter time for steam raisingDthe water tube boiler require lower skill in operating and maintaining
单选题What generally occurs when the land is cooler than the nearby water? （）AA land breezeBA sea breezeCA northerDA prevailing westerly
单选题Under International Rules（）.Aall vessels must carry an after range lightBvessels less than 50 meters in length need not carry an after range lightCvessels stopped dead in the water should turn off their range lightsDvessels over 20 meters in length must carry both range lights from sunset to sunrise
单选题When a tornado moves over the water from land it is called a（）.ATornadoBWaterspoutCHurricaneDCyclone
单选题Large pipes or （） are fitted between the steam and water drums to ensure good natural circulation of water.Afire-tubesBfurnacesCdown-comersDsoot-blowers