boil up
US /bɔɪl ʌp/
UK /bɔɪl ʌp/

1.
ferver, explodir
to become very angry or excited
:
•
His anger began to boil up when he heard the news.
A raiva dele começou a ferver quando ele ouviu a notícia.
•
Tensions are starting to boil up between the two groups.
As tensões estão começando a ferver entre os dois grupos.