表达as clean as a whistle 像口哨一样干净用来形容事物极其干净或某人没任何前科或污点。在用时，可以直接说人或物clean as a whistle。关于这个说法的由来有不少，有人觉得as clean as a whistle曾用来形容剑划过物体时发出的清澈的声音，也有人称，它来自于大家吹奏芦苇或木制哨子时所发出的清脆声音。
例句
Ive never even been issued a speeding ticket my driving licence1 is clean as a whistle.
我从来没收到过一张超速罚单，我的车本上一分都没扣，毫无污点。
Jen is a bit of a neat freak. She keeps her desk clean as a whistle.
珍是一个酷爱整齐的人，她的办公桌一直打扫得极其干干净净。
Youve really tidied it up here its as clean as a whistle!
你真的认真地做了扫除，这里看着特别干净！