英汉词典

1. （用来表示比率、比例等）每，每一
    You use per to express rates and ratios. For example, if something costs £50 per year, you must pay £50 each year for it. If a vehicle is travelling at 40 miles per hour, it travels 40 miles each hour.

    e.g. Social Security refused to pay her more than £17 per week...
           社会保障部门拒绝每周向她支付17英镑以上的钱。
    e.g. Buses and trains use much less fuel per person than cars.
           公共汽车和火车的人均燃料耗费量比轿车小得多。

2. 依照；依据
    If something happens as per a particular plan or suggestion, it happens in the way planned or suggested.

    e.g. When they reach here they complain that they are not being paid as per the agreement...
           来到这里后，他们抱怨工资没有依照协议发放。
    e.g. I approached an Intourist official, as per instructions.
           我按照指示接洽了一位苏联国际旅行社官员。