The research is so designed that once________nothing can be done to change it.


  1. A.
    begins
  2. B.
    having begun
  3. C.
    beginning
  4. D.
    begun
D
該題題干的意思應(yīng)為“研究工作計(jì)劃得如此周密,一旦工作開始,什么事情也改變不了它”?當(dāng)once (或when, while, if, as if, though/although, as, until, until, whether, unless, since等)引導(dǎo)狀語(yǔ)從句時(shí),若從句中的主語(yǔ)與主句中的主語(yǔ)相同(或從句中的主語(yǔ)為it), 且從句的謂語(yǔ)中有be時(shí),可省略從句中的主語(yǔ)和be, 而只保留形容詞?分詞?動(dòng)詞不定式?介詞短語(yǔ)等,故答案為D?
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科目：高中英語(yǔ) 來(lái)源：皇冠優(yōu)化名題　高中英語(yǔ) 題型：050

　　Sweet potatoes are fat-free,high in fiber and full of the vitamins that research suggests reduce your risk of life-shortening diseases．To stay healthy,we must eat more fruits and vegetables,and sweet potatoes are a great source of beta carotene（胡蘿卜素）and other carotenoids．According to a study of the diets of almost 90,000 nurses,eating about one cup a day of fruils and vegetables rich in carotenoids(which the body turns into vitamin A)can cut your risk of stroke in halt and reduce your risk of heart disease by 22 percent．Other resear chsuggests beta carotene protects against breast,lung and stomach cancers．

　　Beta carotene is the most famous member of the carotenoids family．In fact,a medium sized sweet potato contains nearly 12 mg of beta carotene(antiaging experts usually suggest 6 to 11 mg perday)．Sweet potatoes are also a low-fat source of vitamin E．Research has linked high E diets with a lower risk of heart disease．This vitamin pill in an orange jacket also packs a vitamin C punch-it has more C than apricots(a kind of fruit)．Research suggests that vitamin C protects against ailments ranging from cataracts(an eye disease)to cancer．In addition,A UCLA(University of California,Los Angels)study linked high vitamin C diets with a longer life．Recent studies have showed that antioxidant vitamins C,E and beta carotene fight a fierce battle against free radicals（自由基）,which cause cell（細(xì)胞）damage and lead to various illnesses．Therefore,to keep fit,eat more sweet potatoes．

(1)

According to the text,there exists a lot of ________ in sweet potatoes．

[　　]

A．

fiber,beta carotene,other earotenoids,vitamin E and C

B．

beta carotene,other carotenoids,fiber,vitamin A and E

C．

vitamin A,beta carotene,fiber,vitamin E and C

D．

beta carotent,other carotenoids,vitamin A and E

(2)

This text as a whole suggests that eating sweet potatoes can help ________

[　　]

A．

cut your risk of stroke and heart disease

B．

protect against breast,lung and stomach cancers

C．

protect against ailments ranging from cataracts to cancer

D．

you stay healthy and reduce your risk of life shortening diseases

(3)

“This vitamin pill in an orange jacket”in the passage refers to ________

[　　]

A．

sweet potato

B．

vitamin C pill

C．

vitamin E pill

D．

beta carotene

(4)

The best title of this passage might be ________

[　　]

A．

The Vitamin Superstar

B．

On Sweet Potatoes

C．

Beta Carotene and Vitamins

D．

Diet and Disease

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科目：高中英語(yǔ) 來(lái)源： 題型：053

閱讀理解： 　　

閱讀下面短文，從所給四個(gè)選項(xiàng)中，選出最佳答案。

　Can trees talk? Yes——but not in words． Scientists have reason to believe that trees do communicate (互通信息) with each other． Not long ago, resear- chers learned some surprising things． First a willow tree(柳樹)attacked in the woods by caterpillars(毛毛蟲)changed the chemistry of its leaves and made them taste so terrible that the caterpillars got tired of the leaves and stopped eating them． Then even more astonishing, the tree sent out a special vapour — a signal causing its neighbours to change the chemistry of their own leaves and make them less tasty．

　　　Communication, of course, doesn't need to be always in words． We can talk to each other by smiling, raising our shoulders and moving our hands． We know that birds and animals use a whole vocabulary of songs, sounds, and movements． Bees dance their signals, flying in certain patterns that tell other bees where to find nectar(花蜜)for honey． So why shouldn't trees have ways of sending messages?

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[　　]

A． changing its leaves’chemistry

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[　　]

A． like willow trees

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[　　]

A． have a chemical change and become tasteless

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C． They wave their leaves．

D． They make special sounds．

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A． talking

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