英语听力精选进阶版 13855（在线收听）

Olympic drug cheats

Vocabulary

a sample

a small quantity of urine

diuretic

drug that tends to increase the passing of urine

rigorous

extremely thorough

to detect

to discover the existence of

synthetic

artificial

dipped beneath the radar

not been noticed in doping tests

caution

a warning

sophisticated

most complex

potential cheats

athletes who are suspected of taking drugs

to rest at ease

to relax