at a rate of 托福

He's getting through the ironing at a rate of knots.

他熨烫得飞快。

You must have been going at a rate of knots to have finished so soon.

你肯定干得飞快，不然不会这么早就完成了。

The world urban population is rocketing upwards at a rate of 6.5 per cent per year.

世界城市人口以每6.5％的速度急速上升。