n. some duty that is essential and urgent
a. requiring attention or action
a. relating to verbs in the imperative mood
n. 命令, 必要的事, 规则, 祈使语气
a. 命令式的, 急需的, 势在必行的, 强制的
1. It is imperative that you finish your homework before the deadline.
你必须在截止日期之前完成作业。
2. The doctor said it is imperative to get enough rest to recover from the illness.
医生说，恢复健康必须保证充足的休息。
3. In an emergency, it is imperative to remain calm and follow the instructions.
在紧急情况下，保持冷静并遵循指示是非常重要的。