你应该在十点之前完成这项任务。

You should finish the task by ten o'clock.

上学、上班往往从早上很早就开始了，如果你的生物钟不想让你在十点之前醒来，就会比较糟糕。

School and work tend to start early in the morning, and if your body clock doesn't want you awake until 10, you're gonna have a bad time.