Question

有几句英文俚语怎么翻译？

fly on the wall:
Shut up! I think there is a fly on the wall.
kill an elephant:
He asked you to adjust the carburetor, not rebuild the motor. Don't kill an elephant.

Answer 1

fly on the wall: 未被察觉的观察者
Shut up! I think there is a fly on the wall.
别说话！好象有人在偷听。

kill an elephant: 费力气做（不必要的）事
He asked you to adjust the carburetor, not rebuild the motor. Don't kill an elephant.
他让你调调化油器，又没让你改装发动机。别白费力气。

Answer 2

去网上找下翻译机。貌似百度就有。