Question

【题目】 X-rays are high energy waves that are invisible. 【1】For example,doctors can see inside the human body and security guards at airports can see inside your handbag. In 1895,the German scientist,Wilhelm Rontgen,discovered X-rays by accident. He called them X-rays because he hadn't seen such a form of radiation before. 【2】Wilhelm took the first X-ray picture of the bones of his wife's hand after the discovery. In 1901,he received the first Nobel Prize in Physics for his discovery.

X-rays are valuable in medicine because then can see through certain parts of the body. Doctors can take pictures to see which bones are broken or to find out which teeth have holes. The X-rays are strong enough to pass through the skin and muscles,but they cannot pass through hard objects like bones. In the picture,hard objects like bones are white area【3】

There are some situations in which X-rays cannot give you a clear picture. Some organs,for example,may prevent X-rays from showing a broken bone. For this reason,computed tomography(CT)was invented. A person is put inside a scanner,which is a large tube-shaped machine. 【4】 A computer puts together all of these images,which can show doctors more than a normal X-ray can.

【5】Patients must wear protective clothing for the parts of their body that are not X-rayed. Doc- tors and helpers who work with X-ray machines must wear lead aprons and stand behind screens.

A.Then the person is X-rayed from all sides.

B.Objects that X-rays go through appear dark.

C.In mathematics,X means something unknown.

D.An X-ray machine is used to take these pictures.

E.X-rays,however,can also do harm to your body.

F.However,they can be an essential tool for finding out what's wrong with you.

G.They are useful because they can pass through many things that normal light cannot.

Answer 1

【答案】

【1】G

【2】C

【3】B

【4】A

【5】E

【解析】

这是一篇说明文。文章介绍X射线的用途。

【1】根据上文提示“X射线是不可见的高能波。”再根据下文提示“例如，医生可以看到人体内部，机场保安可以看到你的手提包内部。”承接上下文，G项They are useful because they can pass through many things that normal light cannot.（它们很有用，因为它们可以穿过许多普通光不能穿过的东西。）切题。故选G。

【2】根据上文提示“他称它们为X射线是因为他以前从未见过这种形式的辐射。”再根据下文提示“在这个发现之后，威廉给他妻子的手骨拍了第一张X光照片。”承接上下文，C项In mathematics,X means something unknown.（在数学中，X表示未知的东西。）切题。故选C。

【3】根据下文提示“在图片中，像骨头这样的坚硬物体是白色区域。”承接上文，B项Objects that X-rays go through appear dark.（被X射线穿透的物体看起来是黑暗的。）切题。故选B。

【4】根据上文提示“一个人被放进一个扫描仪里，这是一个大型的管状机器。”再根据下文提示“计算机将所有这些图像组合在一起，可以向医生展示比普通X光更多的图像。”承接上下文，A项Then the person is X-rayed from all sides.（然后对病人进行X光检查。）切题。故选A。

【5】根据下文提示“病人身体未被X光照射的部位必须穿防护服。”承接下文，E项X-rays,however,can also do harm to your body.（然而，X光也会伤害你的身体。）切题。故选E。