Meaning trap

slow down

reduce speed

To move or do something more slowly, especially to avoid danger or because you are told to.

phrasal verbB1core

Don't mix these meanings

Same phrase, different job.

reduce speed

To move or do something more slowly, especially to avoid danger or because you are told to.

slow down (become less active)

Another meaning of 'slow down' is 'become less active'; compare the examples to keep the meanings separate.

Notice where the phrase sounds natural.

You should slow down when driving through a school zone.travel
If I notice someone tailgating me on the highway, I usually slow down to let them pass safely.IELTS speaking

Pattern: slow down (no object) | slow down (object)

WrongYou should slow down your speed.

RightYou should slow down.

'Slow down' already means reduce speed — 'slow down your speed' is redundant.

Patternslow down (no object) | slow down (object)

Choose the version that sounds natural in speech.

Stiff Please reduce your velocity near the school.

Natural Slow down near the school.

'Slow down' is the plain everyday verb; 'reduce your velocity' is technical.

Words that usually travel with it.

Not the same as 'stop'—it just means to reduce speed.

slow down (become less active) — Another meaning of 'slow down' is 'become less active'; compare the examples to keep the meanings separate.