become of
to happen to, to occur to.
Then the Witch looked at the big, shaggy Lion and asked, "When Dorothy has returned to her own home, what will become of you?"
ADJ.
active, clear, cold, dull, electronic, fat, fierce, great
The old photograph became dull and faded after sitting in the sun for years.
VERB + BECOME
conduct, doesn't, eyes, pencil, spread, weather
The disease spread rapidly through the village and became a serious threat to public health.
BECOME + NOUN
conflagration, dog, gentleman, mockery, sister, teacher
She decided to become a teacher after working in the hospital for five years.
PREP.
after, in
She became fluent in French after spending two years living in Paris.
ADV.
again, increasingly, quickly
The situation became increasingly difficult to manage as more people got involved.