imperative

剑桥词典

imperative adjective (URGENT)

extremely important or urgent
极重要的；紧急的；迫切的
[ 词或词组后面接一个that从句 ] The president said it was imperative that the release of all hostages be secured . 总统说当前要务是确保所有人质都获释。
[ 动词后面接一个带to的不定式 ] It's imperative to act now before the problem gets really serious . 必须现在就采取行动，而不是等到问题变得难以收拾。

imperative adjective (GRAMMAR)

language   specialized
used to describe the form of a verb that is usually used for giving orders
祈使语气
In the phrase "Leave him alone !", the verb "leave " is in the imperative form . 在句子 Leave him alone! 中，动词 leave 用的是祈使语气。 返回 imperative