1.at rest 休息之中，处于停止状态，处于安宁状态
例句：He lies at rest in the Martyrs' Cemetery.
他在烈士陵园安息着。
2.at risk 处境危险，遭受危险
例句：He saved three children alive at risk of his life.
他拼命救出了三个孩子。
3.at sea level 在海平面上
例句：A unit of pressure equal to the air pressure at sea level, approximately equal to1.01325?05newtons per square meter.
大气压力压力单位，等于海平面上的空气压力，每平方米约为1。01325?05牛顿
4.at sixes and sevens 乱七八糟；不和
例句：I'm all at sixes and sevens about what to do.
我心里七上八下,不知该怎么办。
5.at the expense of 由...付费，由...负担费用；以...为代价，在...受损害的情况下
例句：It is wrong to aim at sheer quantity at the expense of quality.
片面地追求数量而忽视质量是错误的。
6.at the mercy of (at sb.’s mercy) 任凭...的摆布，完全受...的支配
例句：A sailor is at the mercy of the weather.
水手受到天气的摆布。