【文章內(nèi)容簡介】 only strengthen the immunity.”“Similarly the mosquitoes could be used to help treat malaria (瘧疾), perhaps a decade from now,” said the malaria expert.Nearly one million people die each year from malaria—most of them are children—mainly in Africa and Asia, according to the World Health Organization. Now a problem is that no effective vaccine exists. “There is a treatment that works, but it is beyond the reach of people who need to worry about food for tomorrow,” Yoshida said.However, Yoshida expects that the geneticallyengineered mosquito will finally help wipe out the deadly disease in the developing world. “Technically speaking, I believe it’s a matter of 10 years or so, but it’s not clear whether society would accept it,” he said.Another problem is that the geneticallyengineered mosquito may still pick up and spread the infected blood of a person who has already caught malaria. Yoshida’s team is hoping it can solve this problem by developing a mosquito species that kills the malaria virus inside its own body.28. How have scientists turned mosquitoes into carriers of a vaccine?A. By changing their genes.B. By killing the virus in their bodies.C. By letting them bite mice.D. By injecting vaccines into their bodies.29. Which of the following is NOT an advantage of using mosquitoes as vaccine carriers?A. It’s free of charge. B. It’s convenient.C. It’s more effective. D. It’s unnoticeable.30. What can we infer from the last two paragraphs?A. People wele the idea of using mosquitoes to treat malaria.B. Mosquitoes carrying vaccines may still spread malaria.C. It is not long before people will use mosquitoes to get rid of malaria.D. A mosquito can kill the malaria virus inside its own body.31. The main purpose of the passage is to .A. introduce a possible solution to malariaB. encourage people to use mosquitoes to fight against diseasesC. show that Japan has very advanced technologyD. call on people to help people suffering from malaria in Africa and AsiaDTracking wildlife is a tough job. Take the case of a oneeared leopard named Pavarotti.Kasim Rafiq, a wildlife biologist at Liverpool John Moores University. “So I used to get up at the crack of dawn, follow his tracks and try and find him. So one day, I went out, and I was looking for him. And his tracks took me off road through this woodland area...and...”Before he knew it, the wheel of his Land Rover was stuck in a deep hole. He wasted several hours getting it out. And then, on the way back to camp, he came across some local tour guides and their safari guests, who’d had way better luck spotting Pavarotti. “Basically, they laughed and they talked to me that they’d seen him that morning.”Rafiq then realized that tourist wildlife sightings might be an untapped source of information about wild animals.So he and his team worked with a safari lodge in Botswana to analyze 25 000 tourist photographs of wildlife. They pared those data to the estimates they made with traditional wildlife biology methods.It turned out that the estimates from tourists’ photos were just as good as those gleaned (四處搜集) from traditional methods. And the tourists were actually the only ones to see elusive (難以捉摸的) leopards—the researchers would have missed the cats without the citizen science data. The results are in the journal Current Biology.The idea is not to put wildlife researchers out of a job. “The reality is there are so many interesting things we still have to find out about these large carnivores (食肉動物) and so many conservation projects that need to be carried out that we don’t have the time or resources to do them all.” And tourist photos might help make sure that all the local carnivores are spotted.Thanks for listening for Scientific American—60Second Science. I’m Christopher Intagliata.32. What happened to Rafiq when he tracked Pavarotti?A. He was lost in the woods.B. He was trapped in a deep hole.C. He found Pavarotti with tourists’ help.D. He met Pavarotti on the way back to camp.33. Why can biologists trac