国产av不卡一区二区_欧美xxxx做受欧美_成年人看的毛片_亚洲第一天堂在线观看_亚洲午夜精品久久久中文影院av_8x8ⅹ国产精品一区二区二区_久久精品国产sm调教网站演员_亚洲av综合色区无码一二三区_成人免费激情视频_国产九九九视频

進入英語學習論壇下載音頻 去聽寫專區一展身手

Malaysia released about 6,000 genetically modified mosquitoes into a forest in the first experiment of its kind in Asia aimed at curbing dengue fever, officials said on Wednesday.

The field test is meant to pave the way for the use of genetically engineered Aedes aegypti male mosquitoes to mate with females and produce no offspring or ones with shorter lives, thus curtailing the mosquito population.

Only female Aedes aegypti mosquitoes spread dengue fever, which killed 134 people in Malaysia last year.

A similar trial in the Cayman Islands last year - the first time genetically modified mosquitoes have been set loose in the wild after years of laboratory experiments and hypothetical calculations - resulted in a dramatic drop in the mosquito population in a small area studied by researchers.

The plan has sparked criticism by some Malaysian environmentalists, who fear it might have unforeseen consequences, such as the inadvertent creation of uncontrollable mutated mosquitoes.

Critics also say such plans could leave a vacuum in the ecosystem that is then filled by another insect species, potentially introducing new diseases. Government authorities have tried to allay the concerns by saying they are conducting small-scale research and will not rush into any widespread release of mosquitoes.

The Malaysian government-run Institute for Medical Research said it released about 6,000 sterile male lab mosquitoes in an uninhabited forest area in eastern Malaysia on Dec 21.

Another 6,000 wild male Aedes aegypti mosquitoes were also placed in the area for scientific comparison, it said in a statement.

The institute provided few details of the experiment, but said it was "successfully" concluded on Jan 5, and that all the mosquitoes were killed with insecticide.

Questions:

1. How many genetically modified mosquitoes were released?

2. Where was a similar trial held last year?

3. How many people were killed by dengue fever in Malaysia last year?

Answers:

1. 6,000.

2. Cayman Islands.

3. 134.

去聽寫專區一展身手

（中國日報網英語點津 Helen 編輯）

About the broadcaster:

Lee Hannon is Chief Editor at China Daily with 15-years experience in print and broadcast journalism. Born in England, Lee has traveled extensively around the world as a journalist including four years as a senior editor in Los Angeles. He now lives in Beijing and is happy to move to China and join the China Daily team.