I must go back at once.

我必须马上回去。

youdao

"You must go back and get your sleep out," she said.

“你得回去睡一觉。”她说。

youdao

You must go back to your registered permanent residence, and apply for it there.

你必须回到你的户籍所在地申请。

youdao

To understand how all this came about we must go back to when Nepalese began migrating to Bhutan.

CNN: Going Nowhere

One must go back to borrowing (and lending) for a comparably fundamental idea.

ECONOMIST: Letters

They must go back to the core DNA of the brand and ensure that every pot and pan, every slipcover and throw pillow is unique and of the highest quality possible.

FORBES: Move up http://i.forbesimg.com t Move down