English Reference

Phrasal verb

block up

Definition

phrasal verb. to fill a space or a pipe so that nothing can pass through it.

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

Examples

“Leaves often block up the drains in autumn.”

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

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

Examples

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.”

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.

Phrasal verb

Particles

up

Separability

optional

Pattern

block + (object) + up

Synonyms

Antonyms

Grammar

This entry

Level
B2 · Upper Intermediate
Updated

Scan code

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English Reference