gradually become
/ˈɡrædʒuəli bɪˈkʌm/
verb phrase
-
to slowly change into a different state, condition, or identity over time
B1linking verb; followed by an adjective, noun, or past participle
- "The sky gradually became darker."A2
- "With practice, she gradually became more confident."B1
- "The small town gradually became an important center of trade."B2