You must drop your speed in built-up areas.

在房屋密集区必须放慢速度。

《牛津词典》

Aggressive drivers also caused speed to drop because they braked hard at the last moment to avoid driving into the car in front.They then had to drive more slowly to open up a space again.

激进的驾驶员也导致了交通速度的降低，因为他们最后一秒急刹车以避免撞到前面的车辆的时候，他们就会开得更慢以拉大跟车距离。

youdao

The global average connection speed is once again increasing, after an unusual drop in the second quarter.

全球互联网的平均速度在经历过第二季度的不寻常下滑后又再一次提高了。

youdao

The M5 Pro also makes use of True Speed Technology to prevent the drastic performance drop seen in some SSDs after intense or long-term usage.

ENGADGET: Plextor M5 Pro bulges SSD envelope with 94K IOPS and 540MB/s