ENGLISH
REFERENCE

blow up

phr. v..
A2 Elementary Oxford Informal

phr. v.. to explode or to destroy something with an explosion; it can also mean to fill something with air, like a balloon.

phr. v.. to undergo or cause to undergo a sudden, violent expansion or destruction; also used transitively to denote the inflation of an object.


SIMPLE

The soldiers had to blow up the old bridge.

CONTEXTUAL

We need to blow up fifty balloons before the birthday party starts at noon.

COMPLEX

The structural integrity of the building was so compromised that the demolition crew decided to blow up the entire north wing.

Origin

From Middle English blow up, blowe up, dissimilated forms of earlier Middle English upblowen (> English upblow), equivalent to blow + up. Compare West Frisian opblaze (“to blow up, inflate”), Dutch opblazen (“to blow up, inflate”), German aufblähen and aufblasen (“to blow up, inflate”), Swedish blåsa upp (“to blow up, inflate”), Icelandic blása upp (“to blow up, inflate”), Gothic 𐌿𐍆𐌱𐌻𐌴𐍃𐌰𐌽 (ufblēsan, “to blow or puff up”).

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

when it means to inflate, it is usually transitive; when it means to explode, it can be transitive or intransitive.

Teaching tip

mention the informal figurative sense 'to get very angry' (e.g., 'he blew up at me') to show how the idea of an explosion applies to emotions.

Pitfall

He blew the balloon up it.He blew the balloon up.if using a pronoun as the object, it must go between the verb and the particle.

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