The straps cross over at the back and are tied at the waist.

带子在背后交叉，然后系在腰部。

《牛津词典》

I'll tell you when it's safe to cross. You go over to the coke machine, get your coke and come back out. Wait for me to tell you when it's safe to cross back.

我会呆在这儿并留意睡着的孩子，我会告诉你什么时候过去是安全的，你走到可乐机，拿到你的可乐然后站在外面，等着我告诉你什么时候回来是安全的。

youdao

To his surprise, he found that he could cross six of the Bridges without going over any of them twice or going back on himself, but he couldn't cross all seven.

令他惊奇的是，他发现在不走两次或回头路的情况下，只能同时穿过六座桥却不能穿过所有的七座桥。

youdao

Cisco's newest gear is designed to effortlessly cross back and forth over those seams, innately sensing whether a digital packet is video, e-mail or an order and routing it only to the destination that can best use it.

FORBES: Technology

To find its coaches, the program took applications from any teachers in the system who were willing to cross over to the back of the classroom for a couple of years and teach colleagues instead of students.

NEWYORKER: Personal Best

Elano sought to change that trend with a back-post cross that was headed high over the top by Chelsea's Ramires.

BBC: Scotland 0-2 Brazil