1 up in arms 竭力反对；进行武装斗争

The whole village is up in arms about the proposal to build an airport nearby.

全村强烈反对在附近修建机场的计划。

2 at arm's length 保持一定距离

I keep trying to get friendly with the girl who sits next to me. But she keeps me at arm's length.

我一直设法和那个坐在我旁边的女孩友好相处。可是，她老是和我保持一定距离。

3 a shot in the arm 一针强心剂

The Queensland floods are giving a shot in the arm to steel prices.

昆士兰洪灾给钢铁价格打了一针强心剂。

4 an arm and a leg 非常昂贵

She saw a beautiful coat but it cost an arm and a leg.

她看到了一件漂亮的上衣，但它的价格昂贵。