sù
dù
1
speed
2
rate
3
velocity
4
(music) tempo
他是一个很聪明的孩子,学习速度也很快。
He is a very smart child, he learns very quickly.
他的跑步速度很快。
His running speed is very fast.
这城市经济发展速度很快。
The city's economy is developing rapidly.