英语听力精选进阶版 13904（在线收听）

Frog antibiotics

Vocabulary

secreting

releasing

germs

organisms that cause disease

antibiotics

drugs to cure infection

swab

take a small sample from

combat

fight against

drug-resistant

able to remain unaffected by drugs

toxic

poisonous

benign

safe

frog diversity

a variety of types of frog

extinct

no longer existing