用作定语
▲～+n.
It's a crucial decision.这是一个极其重要的决定。
用作表语
▲S+be+～+prep.-phrase
He believes this work is crucial for the welfare of the family.他认为这份工作对家庭的幸福至关重要。
The success of this experiment is crucial to the project as a whole.这次试验的成功是整个工程的关键所在。
It was crucial for the future of our firm.这对我们公司的前途至关重要。
