题目内容

It ________ have snowed last night, ________ it?


  1. A.
    mustn't; did
  2. B.
    couldn't; has
  3. C.
    must; haven't
  4. D.
    must; didn't
D
must表示推测时，反意疑问句由must后面的内容来决定（即以从句中的时间为依据）。
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　　We have met the enemy and he i s our s．We bought him at a pet shop．When monkey-pox, a di sea se u sually found in the African rain fore st suddenly turn s up in children in the American Midwe st, it' s hard not to wonder of the di sea se that come s from foreign animal s i s homing in on human being s．“Mo st of the infection s we think of a s human infection s started in other animal s, ” say s Stephen Mor se, director of the Center for Public Health Preparedne s s at Columbia Univer sity．

　　It' s not ju st that we're going to where the animal s are; we're al so bringing them clo ser to u s．Popular foreign pet s have brought a whole new di sea se to thi s country．A strange illne s s killed I sak sen' s pet s and she now think s that keeping foreign pet s i s a bad idea, “I don't think it' s fair to have them a s pet s when we have such alimited knowledge of them．” say s I sak sen．

　　“Law s allowing the se animal s to be brought in from deep fore st area s without stricter control need changing．” say s Peter Schantz．Monkey-pox may be the wake-up call．Re searcher s believe infected animal s may infect their owner s．We know very little about the se new di sea se s．A new bug(病毒)may be kind at fir st．But it may develop into something harmful．Monkey-pox doe sn't look a major infectiou s di sea se．But it i s not impo s sible to pa s s the di sea se from per son to per son．

(1)

We learn from Paragraph 1 that the pet sold at the shop may ________．

[　　]

A．

come from Columbia

B．

prevent u s from being infected

C．

enjoy being with children

D．

suffer from monkey-pox

(2)

Why did I sak sen advi se people not to have foreign pet s?

[　　]

A．

Becau se they attack human being s．

B．

Becau se we need to study native animal s．

C．

Becau se they can't live out of the rain fore st．

D．

Becau se we do not know much about them yet．

(3)

What doe s the phra se “the wake－up call” in Paragraph 3 mo st probably mean?

[　　]

A．

A new di sea se．

B．

A clear warning．

C．

A dangerou s animal．

D．

A morning call．

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项，选项中有两项为选项．

Ea sy Way s to Keep Your Brain Sharp

　　Everyone i s forgetful, but a s we age, we start to feel like our brain s are slowing down a bit-and that can be a very annoying thing．　　1　　 Read on for some technique s worth trying．

　　1．　　2　　

　　People who regularly made plan s and looked forward to upcoming event s had a 50 percent reduced chance of Alzheimer' s di sea se(老年性痴呆症)， according to a recent study．　　3　　 Something a s simple a s setting a goal to have a weekly coffee date with a friend will do．There' s evidence that people who have a purpo se in life or who are working on long or short-term goal s appear to do better．In other word s, keep your brain looking forward．

　　2．Go for a walk．

　　Mildly rai sed glucose(葡萄糖)level s can harm the area of the brain that help s you form memorie s and phy sical activity can help get blood glucose down to normal level s．In fact, exerci se produce s chemical s that are good for your brain．　　4　　

　　3．Learn something new．

　　Take a Spani sh cla s s online, join a drawing club, or learn to play card s．A study found that mental stimulation limit s the weakening effect s of aging on memory and the mind．But the be st thing for your brain i s when you learn something new and are phy sically active at the same time．　　5　　 Or you can ju st go dancing with your friend s．

A．Focu s on the future．

B．Thi s can be e specially harmful to the aged．

C．It should be something like learning gardening．

D．So take a few minute s each day to do some reading．

E．But don't worry if our schedule i sn't filled with life－changing event s．

F．Luckily, re search show s there i s a lot you can do to avoid tho se moment s．

G．In other word s, when you take care of your body, you take care of your brain．

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