ENGLISH
REFERENCE

block up

phr. v..
B2 Upper Intermediate Oxford

phr. v.. to fill a space or a pipe so that nothing can pass through it.

phr. v.. to obstruct an opening, passage, or pipe completely, preventing the flow of liquids, air, or traffic.


SIMPLE

Leaves often block up the drains in autumn.

CONTEXTUAL

The sink is taking a long time to empty because hair and soap have started to block up the pipes.

COMPLEX

Heavy snowfall during the night threatened to block up the narrow mountain passes, effectively isolating the small village from the rest of the valley.

Particles
up
Separability
optional
Pattern
block + (object) + up
Usage

often used in the passive voice or with physical objects like pipes, noses, or roads.

Teaching tip

contrast with 'block' (the simple verb); adding 'up' emphasizes the completeness of the obstruction or the gradual process of it becoming totally filled.

Pitfall

The drain is block up.The drain is blocked up.when describing the state of the object, you must use the past participle 'blocked' as an adjective.

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