Questions 19 to 21 are based on the conversation you have just heard.
Advertising company.
Businessmen.
C. Advertisement audience.
D. The article buyers.
查看答案
Stem borers are insect pests that often ruin North American corn crops. On some other continents, crop damage by stem borers is controlled by a certain species of wasp. Since these wasps cat nothing but stem borers, importing them into North America will keep crop damage from stem borers under control without endangering other North American insect species. Which of the following is an assumption on which the argument depends
A. Corn is the principal food of stem borers that live on continents other than North America.
B. The wasps are capable of surviving in North America long enough to eat significant numbers of stem borers.
C. No wasp in North America is closely related to the species of wasp that eats stem borers.
D. On continents other than North America, the wasps control stem borers more effectively than does any other pest control measure.
E. Corn crops on continents other than North America are not damaged by any insect pests other than stem borers.
[听力原文]W: I want to see the movie tonight, but it starts at 7, and I have to work until 6.M: I have got an idea, I’ ll pick you up after work and we’ll eat in the Chinese restaurant. What do you learn from this conversation（）
A. The woman will go home for dinner.
B. The woman will not see the film.
C. Both of them will go home before going to the cinema.
D. The man and woman will eat together.
好发于下肢的是( )
A. 丹毒
B. 新生儿皮下坏疽
C. 疖
D. 痈
E. 脓性指头炎
Because adult iguanas on Plazos Island are much smaller than adult iguanas of the same species on nearby islands, researchers assumed that environmental conditions on Plazos favor the survival of relatively smaller baby iguanas (hatchlings) in each yearly brood. They discovered instead that for each of the past three years, 10 percent of the smaller and 40 percent of the larger hatchlings survived, because larger hatchlings successfully evade their predators. Which of the following, if true about Plazos but not about nearby islands, contributes most to an explanation of the long-standing tendency of iguanas on Plazos to be smaller than those of the same age on nearby islands
A. Periodic wind shifts cause extended dry spells on Ptazos every year, putting the larger iguanas, whose bodies require relatively more water, at a great disadvantage.
B. There are exactly three species of iguanas on Plazos but only two species of seagulls that feed on iguanas, and a relatively small percentage of each year’s hatchlings are consumed by seagulls.
C. Wild cats, which were introduced as pets by early settlers and which were formerly major predators of Plazos iguanas, were recently killed off by a disease specific to cats.
D. The iguanas on Plazos are a relatively ancient part of the island’s animal life.
E. Both land and marine iguanas live on Plazos, and the land iguanas tend to be larger than marine iguanas of the same age.
微信支付 
支付宝支付