ahead of time 提前
例句：
I did my homework ahead of time,so I can play tonight.
我提前做了家庭作业，所以今晚可以玩了。
The train has left five minutes ahead of time.
火车提前5分钟离开了。
Thanks to your help,we have completed the project two weeks ahead of time.
多亏了您的帮助，我们提前两周完成了这项工程。