速率的英文：
speed
rate

参考例句：

Beta-blockers alleviate pain and slow the heart rate.
β阻断剂能够减轻疼痛，降低心跳速率。

Tachycardia： Heart rate over 100 (as high as 240) beats per minute.
心搏过速:心搏过速指心搏速率每分钟超过100次(最高可达240次)的情况。

At a rapid clip
以高速率

The velocity has increased
速率增加

Spin-bearing life is sharply reduced at higher operating speeds.
改变圆筒旋转速率就改变被筛选的速率。

Changing the rate of cylinder rotation changes the speed selected.
改变圆筒旋转速率就改变被筛选的速率。

What's the speed of photographic plate?
胶片的感光速率是多少？

Adaptive speed leveling
自适应速率等级调整

PRI (Primary Rate Interface)
初始速率接口

BRI(Basic Rate Interface)
基本速率接口

speed是什么意思：
n. 速度，速率；快速，迅速
v. 迅速前进，快行；促进；加速，使加速

The speed of a train differs greatly from the speed of an airplane
火车的速度与飞机的速度大不相同。

The car is gaining speed.
那辆轿车正在加速。

The worker is timing the speed of the machine.
这名工人正在调整机器的速度。

a dizzy height, speed
使人眩晕的高度、 速度.

Speed the parting guest
祝客人一路顺风

rate是什么意思：
n. 比率，速率；费用
v. 评估；认为；划分等级；值得

cumulative rating
累积收听率

These bonds have an AAA rating.
这些债券的信用度是3A级的。

To rate too low;underestimate.
低估对…估价太低；低估

A Lump Sum Rate of ...
费用合计…

To reduce in rank or rating;demote.
使降级降低级别或降级；使人降级