Phrasal verbs with knock

When you knock something, you hit it with force, and this basic idea of impact runs through most phrasal verbs with this verb. The different particles then show you what happens after that impact or where the force is directed.

Many of these phrasal verbs follow the simple pattern of hitting something so it moves in a particular direction. You can knock someone over by hitting them so they fall backwards, or knock someone down with your car so they fall to the ground. Buildings work the same way – you knock down old houses by hitting them with machinery until they collapse.

The particle "out" creates two common meanings that both involve removing someone from something. You can knock someone out by hitting them unconscious, or eliminate them from a competition – both remove the person from their current situation. This same removal idea appears when you knock off work, meaning you stop and leave.

Some meanings move away from physical hitting. When you knock back a drink, you consume it quickly and forcefully. Prices can be knocked down or knocked off, meaning reduced with the same decisive force as a physical blow. You might even knock someone about different countries during your travels, moving them around from place to place.

The key is recognising that "knock" always suggests something sudden, forceful and decisive happening.