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- because you have an identical twin. Scientists today routinely analyze DNA in blood, saliva, or hair left ______ 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.about

B.in

C.for

D.behind

正确答案:D

答案解析:leave behind是固定搭配，意即：留下。此处leave使用的是过去分词形式。

2、Better Control of TB Seen if a Faster Cure is Found
The World Health Organization estimates that about one-third of all people are infected with bacteria that cause tuberculosis. Most times, the infection remains inactive. But each year about eight million people develop active cases of TB, usually in their lungs. Two million people die of it. The disease has increased with the spread of AIDS and drug-resistant forms of tuberculosis.
Current treatments take at least six months. Patients have to take a combination of several antibiotic drugs daily. But many people stop as soon as they feel better. Doing that can lead to an infection that resists treatment. Public health experts agree that a faster-acting cure for tuberculosis would be more effective. Now a study estimates just how effective it might be. A professor of international health at Harvard University led the study. Joshua Salomon says a shorter treatment program would likely mean not just more patients cured. It would also mean fewer infectious patients who can pass on their infection to others.
The researchers developed a mathematical model to examine the effects of a two-month treatment plan. They tested the model with current TB conditions in Southeast Asia. The scientists found that a two-month treatment could prevent about twenty percent of new cases. And it might prevent about twenty-five percent of TB deaths. The model shows that these ______ would take place between two thousand twelve and two thousand thirty. That is, if a faster cure is developed and in wide use by two thousand twelve.
The World Health Organization developed the DOTS program in nineteen ninety. DOTS is Directly Observed Treatment, Short-course. Health workers watch tuberculosis patients take their daily pills to make sure they continue treatment.
Earlier this year, an international partnership of organizations announced a plan to expand the DOTS program. The ten-year plan also aims to finance research into new TB drugs. The four most common drugs used now are more than forty years old. The Global Alliance for TB Drug Development says its long-term goal is a treatment that could work in as few as ten doses.
【单选题】

A.increases

B.reductions

C.creations

D.collections

正确答案:B

答案解析:上面两句说到“可以防止大约20%的新病例和可能防止大约20%的死亡”，这自然是“降低”，而绝不可能是“增加”，更不是“创作品”、“收藏品”。

3、Breastfeeding Can Cut Cardiovascular Risk
Breastfeeding can reduce the risk of a heart attack or stroke later in life and could prevent hundreds of thousands of deaths each year, researchers said on Friday.
Babies who are breastfed have fewer childhood infections and allergies and are less prone to obesity. British scientists have now shown that breastfeeding and slow growth in the first weeks and months of life has a protective effect against cardiovascular disease.
"Diets that promote more rapid growth put babies at risk many years later in terms of raising their blood pressure, raising their cholesterol and increasing their tendency to diabetes and obesity-the four main risk factors for stroke and heart attack." said Professor Alan Lucas of the Institute of Child Health in London.
"Our evidence suggests that the reason why breast-fed babies do better is because they grow more slowly in the early weeks."
Lucas said the effects of breastfeeding on blood pressure and cholesterol later in life are greater than anything adults can do to control the risk factors for cardiovascular disease, other than taking drugs.
An estimated 17 million people die of cardiovascular disease, particularly heart attack and strokes, each year, according to the World Health Organization.
Lucas and his colleagues compared the health of 216 teenagers who as babies had either been breastfed or given different nutritional baby formulas' They reported their findings in The Lancet medical journal.
The teenagers who had been breastfed had a 14 percent lower ratio of bad to good cholesterol and lower concentrations of a protein that is a marker for cardiovascular disease risk.
The researchers also found that regardless of the child's weight at birth, the faster the infants grew in the early weeks and months of life, the ______ was their later risk of heart disease and stroke. The effect was the same for both boys and girls.
"The more human milk you have in the newborn period, the lower your cholesterol level is, the lower your blood pressure is 16 years later, "Lucas said.
【单选题】

A.smaller

B.greater

C.faster

D.worse

正确答案:B

答案解析:根据前文内容判断，婴儿前期生长越快，他们忠心脏病的风险越大。

4、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 ______ 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.space

B.locations

C.instructions

D.time

正确答案:C

答案解析:根据空白所在的局部结构，以使它们做出相应的动作判断，C（指令）是答案。

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 ______ 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 behind 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.throw

B.prevent

C.create

D.keep

正确答案:B

答案解析:原文中用also may help，说明应填与上文prevent相似的词句。throw：投掷；create：创造；keep：保持，都与之不符，所以是prevent。