By Pallab Ghosh, BBC Science Correspondent

媒體英語會帶大家一起學(xué)習(xí)BBC撰稿人在報道世界大事時常用到的單詞和短語。

Background：科學(xué)家們最近在研究新一代的抗生素。這種抗生素將會使用一種在地球上存活了2億多年的動物 – 青蛙?？茖W(xué)家們將從青蛙體內(nèi)自身的抵抗系統(tǒng)里提煉出一種天然抗生素。

Frogs protect themselves by secreting chemicals that kill germs on their skin. So the theory is that some of these chemicals could be used as antibiotics.

To find out, researchers in the United Arab Emirates asked colleagues across the world to swab any frogs they found and send them their secretions. They received samples from more than six thousand different species and identified more than a hundred germ-killing chemicals.

Because they've not been used to combat human diseases before, it's hoped that they might be able to kill bacteria that had become drug-resistant.

One problem though is that many of these newly-identified chemicals are toxic. So the next step will be to adapt them to make them benign to patients but lethal to bacteria.

The researchers point out that their work highlights the importance of preserving frog diversity. They say that many species whose skin might contain potentially valuable medicinal substances may become extinct soon because of a loss of habitat and water pollution.