They make threats but back down at the first sniff of trouble.

　　他们起先气势汹汹，但一看情形不妙立刻软了下来。

上海419论坛　　I'll take you back down to the valley.

上海419论坛　　我会带你返回下面的`山谷里。

上海419论坛　　His determination and refusal to back down had won the day

　　他的坚定和拒不退让使他赢得了胜利。

　　It's too late to back down now

上海419论坛　　现在打退堂鼓已经太晚了。

　　I drove back down the highway at normal speed

上海419论坛　　我以正常车速沿公路返回。