I drove back down the motorway at normal speed.

我以正常速度沿高速公路往回开。

《柯林斯英汉双解大词典》

Standing still and cooling his brow, he saw a boy running down the hill at topmost speed.

他站着一动不动，冷却着发热的额头，看见一个男孩以最快的速度从山上跑下来。

youdao

The car was barrelling down the street at a crazy speed.

汽车沿着街道发疯一般地高速行驶。

《柯林斯英汉双解大词典》

Before the flight went down, sensors gave conflicting information on air speed to the plane's computers, possibly because of ice.

VOA: special.2009.06.13

And the experimenter is back there with the speed knob and at random intervals he just speeds up the tape of their heart and then slows it down.

实验者回到实验室，带着录音设备,随机地,他加速了心跳的录音,然后又慢下来。

耶鲁公开课 - 心理学导论课程节选

This is caused by faster assistants slowing down to the speed of the average - so as not to embarrass their slower colleagues - while the "slow ones, stay slow", which has an overall effect of dragging down the speed.

BBC: Good queue guide

Buchalter cranked down the speed in TradeWeb so his rivals wouldn't notice how fast it was.

FORBES: Fear, Greed And Technology

Turn down the speed and add the milk, cream, booze, and spices and mix for another 3 minutes.

FORBES: LIVING HIGH ON THE (EGG) NOG