A lemon:
① 一个柠檬
② 不值钱的东西
例句:
The car is a lemon.
这车不值钱。
On the double:
① 双倍
② 加快
例句:
Hurry or we'll miss the train, on the double.
快点,否则我们会错过火车,赶快!
Out to lunch:
① 外出午餐
② 心不在焉
例句:
You must have been out to lunch when you wrote that weird report.
当你做这个奇怪的报告的时候,你一定是神志不清的。