The trees must ________ three times a week.

【判断题】 Could I have three waters, please？

① 正确

② 错误

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【单选题】 4. This kind of plant ____ a lot of water at all times.

① assumes

② limits

③ produces

④ requires

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【多选题】 Among the outstanding inventions of modern times, television___________ must be included.

① clearly

② obviously

③ definitely

④ friendly

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【单选题】 After failing the exams three times, Jack realized that he’d never ____in English.

① see to it

② attain it

③ catch it

④ make it

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【单选题】 Get up! Mary. Tom has _____called you three times this morning.

① yet

② already

③ never

④ seldom

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【判断题】 A: Do you mind if I take three days off this week? B: Never mind.

① 正确

② 错误

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【单选题】 -________ keep water running when you are brushing your teeth or washing your hands, Jack.　　-OK. I know we must save every drop(滴) of water.

① Please

② Why not

③ Don’t

④ do

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【单选题】 Trees mainly serve man in three important ways: They provide him with wood and other products; they provide him shade; and they help to prevent droughts and floods.Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important．In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And besides, he is usually too careless to plant and look after new trees. So the forests slowly disappear.This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil allowing the rain to sink in and also bind(固定) the soil, thus preventing it from being washed away easily；but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When the top-soil is gone, nothing remains but worthless desert.Two thousand years ago，a rich and powerful country cut down its trees to build warships, with which to gain itself an empire．It set up the empire, but, without its trees, its soil became poor and grew weak. When the empire fell to pieces, the home country found itself faced by floods and starvation(饥荒)．Land becomes desert after all trees are cut down because __________.

① roots of trees break up the soil

② no tree keeps the rain and protects the top-soil

③ strong winds bring a lot of sand

④ there are too many rainfalls to make it

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【单选题】 Trees mainly serve man in three important ways: They provide him with wood and other products; they provide him shade; and they help to prevent droughts and floods.Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important．In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And besides, he is usually too careless to plant and look after new trees. So the forests slowly disappear.This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil allowing the rain to sink in and also bind(固定) the soil, thus preventing it from being washed away easily；but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When the top-soil is gone, nothing remains but worthless desert.Two thousand years ago，a rich and powerful country cut down its trees to build warships, with which to gain itself an empire．It set up the empire, but, without its trees, its soil became poor and grew weak. When the empire fell to pieces, the home country found itself faced by floods and starvation(饥荒)．In many places forests slowly disappear because __________.

① many trees have been cut down by man

② new trees are not well looked after

③ man has not paid enough attention to planting trees

④ all the above

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【单选题】 Trees mainly serve man in three important ways: They provide him with wood and other products; they provide him shade; and they help to prevent droughts and floods.Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important．In his eagerness to make money from trees, he has cut them down in large numbers, only to find that without them he has lost the best friends he had. And besides, he is usually too careless to plant and look after new trees. So the forests slowly disappear.This does not only mean that man will have fewer trees. The results are even more serious: for where there are trees, their roots break up soil allowing the rain to sink in and also bind(固定) the soil, thus preventing it from being washed away easily；but where there are no trees, the rain falls on hard ground and flows away, causing floods and carrying away the rich top-soil. When the top-soil is gone, nothing remains but worthless desert.Two thousand years ago，a rich and powerful country cut down its trees to build warships, with which to gain itself an empire．It set up the empire, but, without its trees, its soil became poor and grew weak. When the empire fell to pieces, the home country found itself faced by floods and starvation(饥荒)．Which title best fits the passage?

① Trees and Man

② The Function of Tree Wood

③ How do People do with Trees?

④ The Usage of Tree Roots

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