托福备考阅读精选试题练习2017

　　对于学了许多而对他们无用的词汇的`人们，或学许许多多词汇而不能运用的人们，好象具有一大箱的工具而不能使用的木工一样，比不上一个工具少而能使用自如的木工。以下是小编为大家搜索整理的托福备考阅读精选试题练习2017，希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生考试网!

托福备考阅读精选试题练习2017

　　What unusual or unique biological trait led to the remarkable diversification and unchallenged success of the ants for ever 50 million years? The answer appears to be that they were the first group of predatory eusocial insects that both lived and foraged primarily in the soil and in rotting vegetation on the ground. Eusocial refers to a form of insect society characterized by specialization of tasks and cooperative care of the young; it is rare among insects. Richly organized colonies of the land made possible by eusociality enjoy several key advantages over solitary individuals.

　　Under most circumstances groups of workers are better able to forage for food and defend the nest, because they can switch from individual to group response and back again swiftly and according to need. When a food object or nest intruder is too large for one individual to handle, nestmates can be quickly assembled by alarm or recruitment signals. Equally important is the fact that the execution of multiple-step tasks is accomplished in a series-parallel sequence. That is, individual ants can specialize in particular steps, moving from one object (such as a larva to be fed) to another (a second larva to be fed). They do not need to carry each task to completion from start to finish — for example, to check the larva first, then collect the food, then feed the larva. Hence, if each link in the chain has many workers in attendance, a series directed at any particular object is less likely to fail. Moreover, ants specializing in particular labor categories typically constitute a caste specialized by age or body form or both. There has been some documentation of the superiority in performance and net energetic yield of various castes for their modal tasks, although careful experimental studies are still relatively few.

　　What makes ants unusual in the company of eusocial insects is the fact that they are the only eusocial predators (predators are animals that capture and feed on other animals) occupying the soil and ground litter. The eusocial termites live in the same places as ants and also have wingless workers, but they feed almost exclusively on dead vegetation.

　　1. Which of the following questions does the passage primarily answer?

　　(A) How do individual ants adapt to specialized tasks?

　　(B) What are the differences between social and solitary insects?

　　(D) Why have ants been able to thrive for such a long time?

　　2. The word "unique" in line 1 is closest in meaning to

　　(A) inherited

　　(B) habitual

　　(D) natural

　　3. The word "rotting" in line 4 is closest in meaning to

　　(A) decaying

　　(B) collected

　　(D) cultivated