ENGLISH
REFERENCE

light up

phr. v..
B1 Intermediate Oxford General-service

phr. v.. to make something bright or visible by adding light; also to cause a facial expression of joy or surprise.

phr. v.. to cause a source of light to emit illumination; can also mean to cause a facial expression of joy or surprise, often used metaphorically.


SIMPLE

The lamp lights up the room.

CONTEXTUAL

She lit up the candle to read the letter.

COMPLEX

The fireworks lit up the night sky in a dazzling display.

Particles
up
Separability
inseparable
Pattern
light + up + object
Usage

followed by a direct object indicating what is illuminated, or used intransitively to describe facial expressions.

Teaching tip

contrast with 'illuminate' (formal) and 'brighten' (more general); note the metaphorical use in describing emotions.

Pitfall

The room lit up toThe room lit up with lightthe preposition 'with' is required when specifying the source of light in transitive uses.

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