go back
1．move backwards or away后退；撤离
Go back a step or two；you're too near．后退一两步，你离得太近了。
2．return 返回
Go back to bed，you're too ill to be up．回到床上去，你病重不能起来。
3．（of a clock or watch）be set to an earlier time（钟表）回拨
The clocks go back next week，so it will seem dark sooner．下周钟要往回拨了，所以天似乎要黑得早些。
4．take the mind back in time，in one's thoughts 回顾
Yes，whenever she talks，she always likes to go back to her younger days．是的，她只要一开口，就喜欢回顾她的青年时代。
He went back to his childhood．他回忆了他的童年。
My memory doesn't go back that far．我记不起那么久的事了。
5．date back追溯
The history of those archaeologicalfinds goes back to the 2nd century．这些历史文物的发现可追溯到2世纪。
The story went back to thousands of years ago．这个故事追溯到几千年以前。
6．return to an earlier point（in space，time，a discussion，etc．）回转；回复（前面的话题、讨论等）
She has gone back to her old habits．她又恢复了老习惯。
Let's go back to the subject we were discussing．让我们回到刚才讨论的题目吧。
Now that you've done a year in Medicine，you can't very well go back and start an Arts course．既然你已经学医一年，就不大好回过头来学人文学科了。
Once you decide to emigrate，there will be no going back．一旦你决定移居他国，就不能反悔了。