2021年职称英语考试《综合类》考试共65题，分为单选题。小编每天为您准备了5道每日一练题目（附答案解析），一步一步陪你备考，每一次练习的成功，都会淋漓尽致的反映在分数上。一起加油前行。

1、African wild dogFinding a babysitter while you go out to work is, for example, an inconvenience. For the African wild dog, one of the continent\'s most endangered carnivores （食肉动物), it\'s a matter of life and death. A new research shows that once packs (兽群) fall below a certain size, they are not enough animals to both hunt food and stay at home protecting the young.The African wild dog has declined drastically over the past century. Habitual loss (栖息地的丧失), persecution and unexplained outbreaks of disease have all been blamed. Only 3, 000 to5,000 animals remain, and the species is expected to go extinct within decades if the trend continues.Other large carnivores such as the spotted hyena (鬣狗) face similar pressures, yet are not declining. Now Franck Courchamp of Cambridge University has found a reason why. The dog\'s weakness lies in its social organization.Within each pack of up to 20 adults and pups, only the dominant male and female breed. The remaining animals help raise the pups, cooperating to hunt prey and defend the kill from other carnivores.Because pups can\'t keep up on a hunt, large packs leave an adult behind to protect them from predators (捕猎者), which include lions and hyenas. But leaving a babysitter also carries costs. A smaller hunting party is less able to tackle large prey and to defend the kill. There is also one less stomach in which to carry food back to the den, and one more mouth to feed when they get there.Courchamp investigated this awkward trade-off (权衡) by modeling how the costs of a babysitter change with decreasing pack size. This showed that packs of more than five adults should be able to feed all the pups and still spare a babysitter. But with smaller packs, either the hunting or the babysitting suffers, or the animals have to compensate by increasing the number of hunting excursions which itself carries a cost to the pack.Field observations in Zimbabwe supported the model. Packs of five animals or fewer left pups unguarded more frequently than larger packs did. There was also evidence that when they did leave a babysitter, they were forced to hunt more often.A pack which drops below a critical size becomes caught in a vicious circle (恶性循环), says Courchamp, who is now at Paris-Sud University. "Poor reproduction and low survival further reduces pack size, culminating in (最终造成) failure of the whole pack. " And deaths caused by human activity, says Courchamp, may be what reduce pack numbers to below the sustamable threshold. Mammal ecologist Chris Carbone at London\'s Institute of Zoology agrees. Maintaining the integrity of wild dog packs will be vitalin preserving the species, he says.The African wild dog has been endangered.【单选题】

A.Right

B.Wrong

C.Not mentioned

正确答案:A

答案解析:答案的依据是第2段：在过去的一个世纪里，非洲野狗的数量急剧下降。如果这个势头继续下去的话，在数十年里，这个物种就会灭绝。因此题干的说法是正确的。

2、It seems highly unlikely that she will pass the exam.【单选题】

A.very

B.completely

C.usually

D.mostly

正确答案:A

答案解析:highly和very都表示“非常”；completely：完全地；usually:通常；mostly大概、主要。

3、Women Staying in Mini-Skirts for LongerBritish women are happy nowadays to wear mini-skirts up until the age of40, according to research by Debenhams.Just 20 years ago, few women would dare to wear a mini-skirt. after the age of 33, the store said. "It shows that women now have an increasing confidence in their bodies and are happy to dress accordingly," it added in a statement. "If this trend continues, there\'s no doubt that, within the next decade, women in their mid 40s and early 50s will rightly regard a mini-skirt as an essential part of their everyday wardrobe. "The figures emerged when the store examined the latest age profile of women buying short,36-cm skirts over the past six months. Their results show that it has jumped from an average age of36-years-old at the start of millennium to 40 today. Figures from 1980 showed that on average women stopped buying minis when they reached 33 years old, a figure unchanged from the mid-1960s.The store noted that experts believe that the popularity of intensive gym culture, providing women with well toned bodies for longer may be the reason, The increasing number of British women living on their own may also be a factor.The Debenhams\' study showed that a modern woman\'s love affair with a mini-skirt begins at the age of 14 but that she doesn\'t buy her first one until the age of 16. Instead, she flouts school rules by rolling up the waistband of the school uniform to give the impression of wearing a mini skirt.Skirts get shorter between the ages of 16 and 19, reducing in size from 46 to 36 cm before reaching their shortest, a mere 32 cm, at the age of 23. Skirt length increases slightly between the ages of 23 and 27, rising to 37 cm, possibly due to girls being in their first stable relationship, with no desire to attract attention, the store said.However, it found short skirts suddenly zoom in popularity between the ages of27 and 34, as those early relationships break down, and new relationships are formed. The move into longer skirts begins irreversibly at 40 years old, when 46-cm skirts, still slightly above the knee are the norm. From then on, skirt length increases dramatically, falling below the knee for the very first time since school days at the age of42.Debenhams could most possibly be ____.【单选题】

A.a fashion magazine

B.a lifestyle association

C.an expert on trends

D.a department store

正确答案:D

答案解析:从第2段的第1句话可知，Debenhams是一个百货公司的名称。

4、The policemen acted quickly because lives were at stake.【单选题】

A.in danger

B.in difficulty

C.in despair

D.out of control

正确答案:A

答案解析:因生命危在旦夕，警察迅速行动。本题有一定难度，虽然选项都是常用的固定介词词组，但干扰项干扰较大。At stake和in danger都有“在危险中”的意思，是近义词。B项指“在困难中”，C项指“处于绝望中”，D项指“失去控制”，最佳答案是A。

5、Electric BackpackBackpacks are convenient. They can hold your books, your lunch, and a change of clothes, leaving your hands free to do other things. Someday, if you don\'t mind carrying a heavy load, your backpacks might also power your MP3 player, keep your cell phone running, and maybe even light your way home.Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia and the Marine Biological Laboratory in Woods Hole, Mass, have invented a backpack that makes electricity from energy produced while its wearer walks. In military actions, search-and-rescue operations, and scientific field studies, people rely increasingly on cell phones, global positioning system (GPS) receivers, night-vision goggles, and other battery-powered devices to get around and do their work. The backpack\'s electricity-generating feature could dramatically reduce the amount of a wearer\'s load now devoted to spare batteries, report Rome and his colleagues in the Sept. 9, Science.The backpack\'s electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer\'s back, and the whole pack moves up and down as the person walks. A gear mechanism converts vertical movements of the pack to rotary motions of an electrical generator, producing up to 7. 4 watts.Unexpectedly, tests showed that wearers of the new backpack alter their gaits in response to the pack\'s oscillations, so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize both electric and non-electric versions of the backpack.The backpack could be especially useful for soldiers, scientists, mountaineers, and emergency workers who typically carry heavy backpacks. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren\'t on the market yet, but if you do get one eventually, just make sure to look both ways before crossing the street!The word "springs" in Paragraph 3 means .【单选题】

A.a small stream of water flowing naturally from the earth

B.the season of the year, occurring between winter and summer

C.the act or an instance of jumping or leaping

D.a length of metal wound around, which returns to its original shape after being pushed

正确答案:D

答案解析:springs在此是弹簧的意思。spring是一个多义词：泉水、春天、弹跳。