By vs Until
By 和 Until二则之间的用法区别。
Hi guys! This is Kee from BBC Learning English, and today I'm going to tell you the differences between until and by.
We use until to talk about doing something up to a certain point in time. If I say: I have to take care of my dog until 5pm, it means I will start taking care of my dog now and stop taking care of it at 5pm.
On the other hand, we use by to talk about doing something before a future time or deadline. If I say: I have to finish an essay by 5pm, it means I can start any time but I will make sure that at 5pm I have finished writing the essay. So, I may even finish it at 3pm or any time before 5.
So we use until to describe doing something up to a certain point in time and we use by to describe doing something before a future time or deadline.