It depends

Traveler: Can I catch the three o'clock train to Toronto?

Ticket agent: That depends  on how fast you can run. It left fifteen minutes ago.

看情况

旅行者：我还能赶上3点钟那班到多伦多的火车吗？

售票员：那得看你跑得有多快。火车15分钟前开出。