Dearest Maria, Aren't I terrible, not coming back like I promised?

我至爱的玛丽亚，未能如约返回，我是不是很糟糕？

《柯林斯英汉双解大词典》

He says you're fired if you're not back at work on Friday. And I think he meant it.

他说如果你周五不回来上班的话，就会被解雇。我想他是当真的。

《柯林斯英汉双解大词典》

I did not leave until she came back.

我不会离开直到她回来为止。

youdao

And when he was going out the door, he looked back and said "Well,I do not see anything about that frog that is any better than any other frog."

VOA: special.2009.08.29

Well, I'm not going to follow the details of this argument, but the basic idea goes back to Descartes.

我不打算对这个论证进行详细讨论,只是说一下笛卡尔的基本思想

耶鲁公开课 - 死亡课程节选

If I place my container of gas on the table here, and I come back an hour later, the pressure needs to be the same when I come back Otherwise it's not equilibrium.

如果我把装气体的容器放在桌子上，一小时以后我再回来时,气体的压强应该是不变的,否则它就不是平衡的。

麻省理工公开课 - 热力学与动力学课程节选

But I will not back down from making sure an oil company can contain the kind of oil spill we saw in the Gulf two years ago. (Applause.) I will not back down from protecting our kids from mercury poisoning, or making sure that our food is safe and our water is clean.

WHITEHOUSE: 2012 State Of The Union Address Enhanced Version

Personally I do not think I would back it - even though I am not a diver and do not condone diving.

BBC: SPORT | Football | Kevin Nolan column

But I will not back down on the basic principle that, if Americans can't find affordable coverage, we will provide you with a choice.

CNN: Obama offers health care details in speech to Congress