为了保持专业，她总是与同事保持距离。

She always ___keeps her colleagues ___at ___arm's ___length to maintain professionalism.

起初，他与新邻居保持距离，但很快他就对他们热情起来了。

Initially, he ___kept his new neighbors ___at ___arm's ___length, but soon he warmed up to them.

在商业中，与潜在竞争对手保持距离是明智的。

It's wise to ___keep potential rivals ___at ___arm's ___length in business.