take the plunge
US /teɪk ðə plʌndʒ/
UK /teɪk ðə plʌndʒ/

1.
采取行动, 下定决心
to decide to do something important or difficult that you have been thinking about for a long time
:
•
After years of deliberation, they finally decided to take the plunge and buy a house.
经过多年的深思熟虑,他们最终决定采取行动买房。
•
She was nervous, but she knew it was time to take the plunge and start her own business.
她很紧张,但她知道是时候下定决心创办自己的公司了。