ENGLISH
REFERENCE

knock up

phr. v..
B2 Upper Intermediate Oxford British English Informal Slang

phr. v.. to wake someone by knocking on their door — often used in informal British English.

phr. v.. to wake someone by knocking; also used informally to mean 'to create or produce something quickly' (e.g., 'knock up a report'). Marked British informal / slang.


SIMPLE

He knocked up his friend at 7 AM.

CONTEXTUAL

She had to knock up her roommate because they were late for work.

COMPLEX

The journalist knocked up a detailed report in under an hour, impressing the editor.

Particles
up
Separability
inseparable
Pattern
knock + up + object
Usage

typically followed by a person or thing being created or woken.

Teaching tip

contrast with 'wake up' (more direct) and 'produce' (formal alternative); note the informal use of 'knock up' meaning 'create quickly' is limited to British English.

Pitfall

He knocked up.He knocked up his friend.the phrasal verb requires an object to indicate who or what is being knocked up

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