I'll back you up one hundred percent no matter what happen.

无论发生什么 ，我都会百分之百支持你。

youdao

I'll back you up if they don't believe you.

如果他们不相信你，我会为你作证。

《牛津词典》

Eg. I'll back you up all the way.

我完全支持你。

youdao

"I reckon you'll be goin' back up to the cabin, along with the cart," said Ariela.

VOA: special.2009.11.14

Let me take you back to the seventeenth century, up to the very beginning of the literary reception of John Milton.

让我把你们带回到17世纪，约翰·弥尔顿刚在文学领域为人所知的时候。

耶鲁公开课 - 弥尔顿课程节选

If you scroll back up on the printout or screen here, you'll see that you can actually not only declare function's prototypes, their general structure.

如果我回滚到打印输出或者这个屏幕，你们将看到你们不仅可以声明函数的原型,它们的一般结构。

哈佛公开课 - 计算机科学课程节选

If you are absolutely certain you are right no matter what, the one person who will always back you up is yourself.

FORBES: 5 Tips to Start Your Business

Start by choosing financial institutions that back you up with strong guarantees.

FORBES: Financial Fraud Is Growing, Post Madoff

No complaint here, right? (Laughter.) You give your all and ask very little in return, only that we back you up so our troops can do their job.

WHITEHOUSE: The First Lady Announces New Funding for Military Families