2019年职称英语考试《理工类》考试共65题，分为单选题和多选题和判断题和计算题和简答题和不定项。小编为您整理完形填空分析5道练习题，附答案解析，供您备考练习。

1、Cell Phone Lets Your Secret Out
Your cell phone holds secrets about you. Besides the names and numbers that you've programmed into it, traces of your DNA linger on the device, according to a new study.
DNA is genetic material that appears in every cell. Like your fingerprint, your DNA is unique to you- ______ you have an identical twin. Scientists today routinely analyze DNA in blood, saliva, or hair left behind at the scene of a crime. The results often help detectives identify criminals and their victims. Your cell phone can reveal more about you than you might think.
Meghan J. McFadden, a scientist at McMaster University in Hamilton, Ontario, heard about a crime in which the suspect bled onto a cell phone and later dropped the device. This made her wonder whether traces of DNA lingered on cell phones even when no blood was involved. So she and colleague Margaret Wallace of the City University of New York analyzed the flip open phones of 10 volunteers. They used swabs to collect invisible traces of the users from two parts of the phone: the outside, where the user holds it, and the speaker, which is placed at the user's ear.
The scientists scrubbed the phones using a solution made mostly of alcohol. The aim of washing was to remove all detectable traces of DNA. The owners got their phones back for another week. Then the researchers collected the phones and repeated the swabbing of each phone once more.
The scientists discovered DNA that belonged to the phone's speaker on each of the phones. Better samples were collected from the outside of each phone, those swabs also picked up DNA that belonged to other people who had apparently also handled the phone. Surprisingly, DNA showed up even in swabs that were taken immediately after the phones were scrubbed. That suggests that washing won't remove all traces of evidence from a criminal's device. So cell phones can now be added to the list of clues that can clinch a crime scene investigation.
【单选题】

A.because

B.unless

C.although

D.still

正确答案:B

答案解析:上文的意思是：如同指纹，你的DNA是独一无二的。因此，此处必须选择unless，其他选择均不符合句义，也违背了我们对DNA的基本常识。

2、An Intelligent Car
Driving needs sharp eyes, keen ears, quick brain, and coordination between hands and the brain. Many human drivers have all. these and can control a fast-moving car. But how does an intelligent car control itself ?
There is a virtual driver in the smart car. This virtual driver has "eyes," "brains", "hands" and "feet", too. The mini-cameras on each side of the car are his "eyes," which observe the road and conditions ahead of it. They watch the traffic to the car's left and right. There is also a highly automatic driving system in the car. It is the built-in computer, which is the virtual driver's "brain". His "brain" calculates the speeds of ______ moving cars near it and analyzes their positions. Basing on this information, it chooses the right line for the intelligent cars, and gives instructions to the "hands" and "feets" to act accordingly. In this way, the virtual driver controls his car.
What is the virtual driver's best advantage? He reacts rapidly. The mini-cameras are sending images continuously to the "brain". It completes the processing of the images within 100 milliseconds. However, the world's best driver at least needs one second to react. Besides, when he takes action, he needs one more second.
The virtual driver is really wonderful. He can reduce the accident rate. considerably on expressway. In this case, can we let him have the wheel at any time and in any place? Experts warn that we cannot do that just yet. His ability to recognize things is still limited. He can now only drive an intelligent car on expressways.
【单选题】

A.another

B.other

C.each other

D.one another

正确答案:B

答案解析:选项B和C都是“彼此、相互”，互为近义词，所以相互排除掉；空白后出现的是复数名词(cars)，因此答案是B（another修饰可数名词的单数）。

3、An Intelligent Car
Driving needs sharp eyes, keen ears, quick brain, and coordination between hands and the brain. Many human drivers have all. these and can control a fast-moving car. But how does an intelligent car control itself ?
There is a virtual driver in the smart car. This virtual driver has "eyes," "brains", "hands" and "feet", too. The mini-cameras on each side of the car are his "eyes," which observe the road and conditions ahead of it. They watch the traffic to the car's left and right. There is also a highly automatic driving system in the car. It is the built-in computer, which is the virtual driver's "brain". His "brain" calculates the speeds of other moving cars near it and analyzes their positions. Basing on this information, it chooses the right line for the intelligent cars, and gives instructions to the "hands" and "feets" to act accordingly. In this way, the virtual driver controls his car.
What is the virtual driver's best advantage? He reacts rapidly. The mini-cameras are sending images continuously to the "brain". It completes the processing of the images within 100 milliseconds. However, the world's best driver at least needs one second to react. Besides, when he takes action, he needs one more second.
The virtual driver is really wonderful. He can reduce the accident rate. considerably on expressway. In this case, can we let him have the wheel at any time and in any place? Experts warn that we cannot do that just yet. His ability to recognize things is still ______. He can now only drive an intelligent car on expressways.
【单选题】

A.unknown

B.few

C.untested

D.limited

正确答案:D

答案解析:空白所在的句子说“他识别不同东西的能力仍然还……”，空白后句说“他现在只能驾驶智能车在高速路上行驶”。既然能在高速路上行驶，则其应该具备一定识别物体的能力，而且应该已经经过检测，因此排除A（未知的）和C（未经试验的）；few应该修饰可数名词的复数形式，而句子主语（被修饰词）是单数，因此排除B，答案是D（有限的）。

4、Seeing Red Means Danger Ahead
The color red often means danger and by paying attention, accidents can be prevented. In the future, the color red also may help prevent danger at construction sites. Thanks to new work by engineers, bridge supports or other kinds of materials could one day contain a color switching material. It will turn red before a structure collapses or falls apart.
The secret ______ the color switching material is a particular type of molecule. A molecule is a group of atoms held together by chemical bonds. Molecules come at all shapes and sizes, and make up everything. You can see, touch or feel. How a molecule behaves depends on what kinds of atoms it contains, and how they're held together.
When a polymer (聚合物) containing a color switching molecule called a mechanophore (机械响应性聚合物) which is about to break, it produce a color. When a polymer with mechanophore molecules becomes "injured" or weak, one of the mechanophore bonds breaks and the material turns red. "It's a really simple detection method. "says Nancy Sottos, one of the scientists who worked on the project. Sottos and her team tested the color switching polymers in their lab. The test results proved encouraging.
There is a way to get rid of the color light when a bright light is shone on the mechanophore.
The broken bond is fixed and the red color disappears. This "self-healing" may be a problem for engineers. They need to use the color changer in big construction projects that will be outside in sunlight. And sunlight will make the mechanophore's warming system useless. Sottos and her fellow scientists still have a lot of work to do before the color switching molecules can be used outside the lab.
【单选题】

A.on

B.behind

C.under

D.down

正确答案:B

答案解析:习惯用法，secret behind指什么东西背后的秘密；under也有底下的意思，但更多是强调地理空间上的；用于抽象事物，多用behind。

5、Seeing Red Means Danger Ahead
The color red often means danger and by paying attention, accidents can be prevented. In the future, the color red also may help prevent danger at construction sites. Thanks to new work by engineers, bridge supports or other kinds of materials, could one day contain a color - changing material. It will turn red before a structure collapses or falls apart.
The secret behind the color - changing material is a particular type of molecule (分子). A molecule is a group of atoms (原子) held together by chemical bonds. Molecules come in all shapes and sizes and make up everything you can see, touch or feel. How a molecule behaves depends on what kinds of atoms it contains and how they're held together.
When a polymer (聚合物) containing a color - changing molecule called a mechanophore (机械响应性聚合物) is about to break, it produces a color. When a polymer with mechanophore molecules becomes "injured" or weak, one of the mechanophore bonds breaks and the material turns red. "It's a really simple detection method," says Nancy Sottos, one of the scientists who worked on the project. Sottos and her team tested the color - changing polymers in their lab. The test results proved encouraging.
There is a way to get rid of the red color light. When a bright light is shone on the mechanophore, the broken bond is fixed and the red color _____. Thus "self - healing" may be a problem for engineers. They need to use the color - changer in big construction projects that will be outside, under sunlight. And sunlight will make the mechanophore's warning system useless.
Sottos and her fellow scientists still have a lot of work to do before the color - changing molecules can be used outside the lab.

【单选题】

A.repairs

B.controls

C.finishes

D.disappears

正确答案:D

答案解析:本题有一·定难度，关键在理解好文章上下文意义，文章此处是说“红色消失了”，答案是D。