“on the edge of seat”别理解成“在座位的边缘”，其正确的含义是紧张，激动。

【例句】
It's not going to win any awards, but the film certainly kept us on the edge of our seat from start to finish.
这部电影不会获得任何奖项，但这部电影肯定让我们从头到尾都非常激动。

They were both playing amazing tennis. Everyone was on the edge of their seats the entire time.
他们打网球都打得很好。整个过程中，每个人感到非常紧张。