单选题Why do some frogs change the pitch of its calls?ATo be different from others.BTo attract a female frog.CTo tend out messages.DTo go against traffic noises.
单选题
Why do some frogs change the pitch of its calls?
A
To be different from others.
B
To attract a female frog.
C
To tend out messages.
D
To go against traffic noises.
参考解析
解析：
由第三段“…further away from the traffic noise and this increases the distance over which it can be for heard,”得知青蛙改变音高是为了避免噪音干扰。
由第三段“…further away from the traffic noise and this increases the distance over which it can be for heard,”得知青蛙改变音高是为了避免噪音干扰。
相关考题：
You have failed several times. Why not ________ some other way?(A) try doing it(B) to try to do it(C) that you try it(D) having tried
Why does it take long for people to change their food?A． Because labs are not easily accessible to researchers.B． Because some people are reluctant to accept the new diet.C． Because food consumption is a culture of conservation.D． Because some scientists are against the growing lab meat.
Parallelism is used in ________.A、It is women who can bring empathy, tolerance, insight, patience, and persistence to government …B、The women of a nation mold its moral, its religions, and its politics by the lives they live.C、Why are women thought of as secretaries, not administrators? Librarians and teachers, but not doctors and lawyers?D、“It is a far, far better thing that I do, than I have ever done …”
What are they?()? It’s a secret. But I’ll give you some hints, anyway.A、Is it a secretB、Can I have an idea about themC、Why do you keep it a secret
If a company wants to see its products_____, it should do some world market report first. A、internationalizeB、internationallyC、internationalD、internationalization
Why do some people oppose cloning?() A.It is not perfectB.It is against our traditional ethics and moralityC.It is against the natural lawD.It may devaluate real life
_____ of the controllable pitch propeller enables the blades to be moved to change the pitch angleA.An external mechanismB.An internal mechanismC.An interlock deviceD.A hunting gear system
Your personal history says you've been working at the ** company for the past two years. Why do you want to change jobs?
Why did the villagers agree to sell frogs?A. The frogs were easy money.B. They needed money to buy visitors.C. They wanted to please the visitors.D. The frogs made too much noise.
29． Why do people like teleshopping?A． Because they like watching TV．B． Because they can do some shopping at home，C． Because they like the heavy traffic．D． Because they think the things on TV are good．
why did the villagers agree to sell frogs ?A the frogs were easy moneyB They needs money to buy medicineC they wanted to plwase the visitorsD．the forgs made too much noise
Pitch variation is known as __________ when its patterns are imposed on sentences.A.intonationB.toneC.pronunciationD.voice
Why do some people choose self-catering accommodation? __________A.To experience a warmer family atmosphereB.To enrich their knowledge of EnglishC.To entertain friends as they likeD.To enjoy much more freedom
问答题◆Topic 10: Government’s Control of Violence in Media Questions for Reference: 1. What negative effects could be brought by the violence in films and on television to our society according to your observation? 2. Do you agree that the government’s control of the amount of violence in films and on television would limit our right of free speech? Why /Why not? 3. Some people put that it is in our best interest as a society for the government to censor broadcast media for violence. Do you think so? Why /Why not?
问答题◆Topic 8: Is education Losing its Value? Questions for reference: 1. Some people think that this increased access to education is devaluing degrees. What’s your point of view? 2. What can the degrees bring to people? 3. Do you think it’s necessary to have increased emphasis on degrees in our society? Why?
问答题Q6: Do you think the location of a company’s premises is important for its competitiveness? (Why?/Why not?)
问答题Q7: Do you think it will become increasingly common for companies to relocate some activities to other countries? (Why?/Why not?)
问答题There is one passage in this section with 5 statements. Go over the passage quickly and answer the questions on the Answer Sheet. For questions 1-5, mark Y (for YES) if the statement agrees with the information given in the passage; N (for NO) if the statement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. When was the last time you saw a frog? Chances are, if you live in a city, you have not seen one for some time. Even in wet areas once teeming with frogs and toads, it is becoming less and less easy to find those slimy, hopping and sometimes poisonous members of the animal kingdom. All over the world, even in remote jungles on the far side of the globe, frogs are losing the ecological battle for survival, and biologists are at a loss to explain their demise. Are amphibians simply over-sensitive to changes in the ecosystem? Could their rapid decline in numbers be signalling some coming environmental disaster for us all? This frightening scenario is in part the consequence of a dramatic increase over the last quarter of a century in the development of once natural areas of wet marshland: home not only to frogs but to all manner of wildlife. Yet, there are no obvious reasons why certain frog species are disappearing from rainforests in the Southern Hemisphere which are barely touched by human hands. The mystery is unsettling to say the least, for it is known that amphibian species are extremely sensitive to environmental variations in temperature and moisture levels. The danger is that planet Earth might not only lose a vital link in the ecological food chain (frogs keep populations of otherwise pestilent insects at manageable levels), but we might be increasing our output of air pollutants to levels that may have already become irreversible. Frogs could be inadvertently warning us of a catastrophe. An example of a bizarre occurrence regarding a species of frog dates from the summer of 1995, when “an explosion” of multi-coloured frogs of the species Rana klepton esculenta occurred in the Netherlands. Normally these frogs are brown and greenish-brown, but some unknown contributory factor is turning these frogs yellow and / or orange. Nonetheless, so far, the unusual bi- and even tri-coloured frogs are functioning similarly to their normal-skinned contemporaries. It is thought that frogs with lighter coloured skins might be more likely to survive in an increasingly warm climate due to global warming. One theory put forward to explain extinct amphibian species that seems to fit the facts concerns the depletion of the ozone layer, a well-documented phenomenon which has led to a sharp increase in ultraviolet radiation levels. The ozone layer is meant to shield the Earth from UV rays, but increased radiation may be having a greater effect upon frog populations than previously believed. Another theory is that worldwide temperature increases are upsetting the breeding cycles of frogs. Statements: 1．Biologists are unable to explain why frogs are dying out. 2．Attempts are being made to halt the development of wet marshland. 3．Frogs are important in the ecosystem because they control pests. 4．It is not known why Dutch frogs are changing colour. 5．It is a fact that frogs’ breeding cycle has been upset by worldwide increases in temperature.
单选题Most tree frogs change colors from time to time to fit in with its environment.AMostBchangeCfrom time to timeDits
判断题The most powerful signal of stress is a change of pitch on the vowel.（）A对B错