单选题
The empty house, in a middle-class corner of southern California, is two storeys high and boasts a three-car garage. Roses bloom around a kidney-shaped swimming pool, which is green with algae. Bill Bobbitt, a county inspector, dips a ladle into the water and brings up half a dozen wriggling larvae. Mosquitoes, and the West Nile virus that some of them carry, are thriving in California's plunging property market. West Nile virus arrived in America in 1999 and made it to California three years later. Since then it is known to have infected 2,300 people in the state, of whom 76 have died. In Orange County this is the worst summer yet. By this point last year officials there had discovered nine birds that had been killed by West Nile virus and not one infected mosquito. So far this year they have found 219 infected birds and 75 infected mosquitoes. Some of this rise is due to better testing and co-operation with the animal services department, which receives most reports of dying birds. But a much bigger cause is the housing crunch. Fully 63,000 homes were foreclosed in California between April and June, according to DataQuick, a property data services outfit. In the past year the number of Orange County homeowners who have defaulted on their mortgages has more than doubled. Empty houses mean untended pools. Untended pools quickly breed mosquitoes. Dead birds are also piling up in neighbouring counties like Los Angeles, San Diego and San Bernardino, which also have high foreclosure rates. Last week 170 infected mosquitoes were discovered in the state as a whole-the highest tally ever. So far this year i3 human infections have been reported in California, but the numbers are expected to grow rapidly as the summer moves on. John Rusmisel, president-elect of the board responsible for killing the critters, says a peak in infected mosquitoes is generally followed, two or three weeks later, by a peak in human cases. In theory, owners are supposed to keep their properties in decent shape whether they live there or not. California has even passed a bill fining banks and mortgage companies that seize properties and then allow pools to fester. But Mr Bobbitt isn't waiting for the lawyers. He has treated the pool in Santa Ana with oil and synthetic growth hormones, which will keep the mosquitoes adolescent, preventing breeding. Then he tips in a few dozen mosquito fish (Gambusia affinis), which begin happily launching larvae. You can buy a lot of the fish for what a lawyer charges per hour, and some authorities, with commendable creativity, even provide them free to help control the pests.
单选题
According to the text, what is the main reason of quick breed of mosquitoes? A. House crunch. B. Inadequate caring of the houses. C. Warm and humid weather. D. More reports of dying birds occur in California.
【正确答案】
A
【答案解析】本题重点在于第三段中的“some…is due to…”和“a much bigger cause…”。由此可以判断后者应该是主要原因，故应当选择A。“housing crunch”指楼市下滑。B项也正确，但是由于楼市下滑引起的；C项文中没有说明；D项则是病毒流行的一个征兆，并非原因。
单选题
Which is correct according to the second paragraph? A. Mosquitoes carrying West Nile virus was spotted last year. B. Death caused by West Nile virus has exceeded 1000. C. West Nile virus has circulated in US for about 10 years. D. More than 200 birds are reported to die of West Nile virus.
【正确答案】
C
【答案解析】A项，文中说“last year…not one infected mosquito”，故A项错误。B项，文中说“of whom 76 have died”，故也错误。C项，“West Nile virus arrived in America in 1999”，距今约有十年，故正确。D项，文中是说有219 infected birds，并未说明是否全部死亡，故错误。
单选题
Why are there so many houses left untended? A. Property market is plunging sharply. B. They are foreclosed and banks and mortgage companies that seize properties do not intend to tend them. C. High fees are needed in tending houses. D. Owners do not live there temporarily.
【正确答案】
B
【答案解析】本题结合第三段作答。C项在文中未说明，故不选。D项虽是房子的现状，但并非导致无人照看房子的原因，且后文也说“In theory，owners are supposed to keep their properties in decent shape whether they live there or not”。难点在于A、B选项。大体上看，A、B选项都是正确的，B项是比较直接的原因，而A项则是导致B项出现的更深一层次的原因，从与题干的结合度来讲，当选B为宜。
单选题
What does "wriggling larvae" refer to in the first paragraph? A. A kind of fish that can eat mosquitoes. B. A kind of bird that dies of West Nile virus. C. Mosquitoes in adolescence. D. A kind of insect that can live in the water.
单选题
Which of the following is NOT the measure taken to combat mosquitoes? A. The state congress passed a bill fining those who do not tend houses. B. Oil and synthetic growth hormones are used to keep the mosquitoes adolescent, preventing breeding. C. Fish that can eat larvae are used. D. Authorities help the owners with pest control on reasonable charges.