Meaning 1 · most common
become visibly happier
If someone's face lights up, it suddenly shows happiness or excitement.
Example
A: What did she say when you told her the news?
B: Her face lit up, and she gave me a big hug.
Tell it apart
light up — 2 meanings
One phrase, 2 meanings. Learn them one at a time, then test yourself.
phrase2 meanings
Meaning 2
make someone feel excited
To light someone up is to make them feel happy, excited, or inspired.
Example
A: Why does he volunteer every weekend?
B: Helping older people just lights him up.
Tell it apart
Spot the meaning
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Read the sentence, then pick the meaning that's in play.
Turn this into speaking practice
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