【问】 at a rate of与at the rate of哪个用法正确?

【答】 两个用法都是正确的，而且意义相同。请考察下面的实例：

1. The train was now going at a rapid rate. (Davies)

火车那时正快速行驶。

2. The train was going at a rate of 80 kilometers an hour. (NAECD)

火车正以每小时八十公里的速度行驶。

3. at the rate of ＄ 20 an hour(CGEL)

以每小时20美元的价格(工资)

4. This money is taxed at the rate of 59%...(EED)

这笔钱以59%的税率上税……