题目内容

【题目】If the dog hadn't woken us, we wouldn't have noticed the fire and it __________ to the house next door.

A. could spread

B. should have spread

C. would spread

D. might have spread

【答案】D

【解析】句意:如果狗没有叫醒我们,我们也就不会注意到火,它可能会蔓延到隔壁的房子。表示对过去可能性的推测,用might have spread。

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【题目】 Have you wondered why you have two eyes and why they are set close together on the front of your face? The reasons are simple and important to the way you see the rest of your world.

Your eyes are like two small cameras. A camera catches an image of an object and records it on film.Similarly,when you look at something,each eye takes in what it sees and sends this image to the back of the eyeball.Because your eyes are set close together,they view the world from about the same height but from slightly different angles. Working as a team, the eyes send the images to your brain, which puts them together into a single, centered image.

Seeing in stereo means seeing with two eyes working together,which is called stereoscopic sight.This allows you to view the world in three dimensions,or 3-D.Seeing depth helps you to judge the distance between you and the objects you see and to adjust to the changing angle at which you see something as you move closer to or farther away from it.If images are coming from only one eye, however,only two of these dimensions-height and width-can be perceived.A world seen with one eye is thus two-dimensional,as in a photograph.

Now consider why your two eyes are on the front of your face.Think of other animals with this same arrangement.They are all animals that hunt,like lions and wolves.Their eyes face directly in front of them.This provides a field of sight about 180 degrees wide,which is called binocular sight.On the other hand,animals that are hunted have eyes on the sides of the head,which provides nearly 360-degree field of sight.In order to stay alive,they need to see things coming from the sides and from behind.However,without stereoscopic sight,they have difficulty determining how far a danger is.

With sight both stereoscopic and binocular,humans share with animal hunters the ability to see from side to side and to accurately determine the distance.If you think it would be great to have another type of sight,perhaps with hundreds of tiny eyes like many insects do,think again! Each tiny insect eye sees only a tiny part.Besides,what if you needed glasses? Be glad for the eyesight that you have.

【1According to the passage,an eye is like a camera because both

A. can record images

B. can imagine objects

C. provide centered images

D. work at the same height

【2Stereoscopic sight is a result of having

A. a three-hundred-sixty-degree field of sight

B. hundreds of eyes,all seeing parts of an image

C. two eyes close to one another that work together

D. one eye on either side of the head,each seeing a different image

【3】The author implies that “seeing in stereo”

A.is similar to the way cameras work

B.is an ability humans are fortunate to have

C.would be better for a wider field of sight

D.helps people to have better sight than animals

【题目】Humans aren’t the only ones getting a buzz from coffee.Caffeine can improve memory among honeybees and lead to better pollination(授粉).According to a recent study published in the journal Science.

The study was conducted by a team of researchers at Newcastle University in the United Kingdom.They found that the nectar(花蜜)of some flowers,such as those from grapefruit and lemon plants,as well as certain coffee flowers,contains low doses of caffeine.To get bees to feed on these flowers,the team trained the insects to associate food with the smell of the flowers.They also trained another group of bees to feed on nectar from flowers that were sweetened with a sugar, but did not contain caffeine.After 24 hours,the bees trained on caffeinated flowers returned to these plants three times as often as those trained on the sweetened flowers returned to the uncaffeinated plants.

Professor Geraldine Wright led the researchers.“Remembering floral traits(花部特征)is difficult for bees to perform at a fast pace as they fly from flower to flower and we found that caffeine helps the bee remember where the flowers are,”Wright said in a statement.

Improved memory led to the better pollination.That’s because once bees sip the caffeine nectar, they continue to look for more coffee plants to pollinate.This also suggests that caffeine plays a role in improving the bees’ability to search for food.

Researchers found that caffeine’s effect on the bee brain is similar to its effect on mammals.“The change is similar to that produced by caffeine in neurons(神经元)associated with learning and memory in the rat brain,”Wright said.

span>Bee populations have declining since 2007.The dramatic drop in the insects’numbers has serious effects for ecosystems and the farming industry.Bees are needed in the reproduction of crops and spreading wild flower species.Understanding what keeps bees buzzing could help to make sure that the insects are able to remember and pollinate their favorite flowers.

【1】Which of the following is mentioned in the passage?

A.Caffeine has no effect on the rat brain.

B. Bee population has been increasing.

C.The nectar of lemon plants contains caffeine.

D.Bees dislike nectar from sweetened flowers.

【2】After reading the passage,John,who works in the farming industry, will probably feel________.

A.annoyed B.angry C.nervous D.excited

【3】Which of the following relationship is correct according to the passage?

A.improved memory—caffeine nectar—better pollination

B.caffeine nectar—improved memory—better pollination

C.improved memory—better pollination—caffeine nectar

D.caffeine nectar—better pollination—improved memory

【4】What section of a newspaper may this passage be taken from?

A.Science B.Education

C.Culture D.Sports

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