the feeling of excitement or nervousness that you have when you are waiting for something to happen and are uncertain about what it is going to be

She kept him in suspense for several days before she said that she would marry him. 她让他焦急难耐地等了好几天，才告诉他愿意嫁给他。

The suspense is killing me (= I am extremely eager to know what is going to happen). 真是急死我了。

There is a gradual build-up of suspense throughout the film, until it comes to an unexpected ending. 这部电影自始自终悬念在一步步加深，最后的结局很出人意料。