because the dogs feel thin ice underfoot and won't lead travellers into trouble.因为狗对薄冰很敏感能保护人类避免危险

lead into:通往, 引入

This gate leads into the courtyard.

这门通向院子。

A policy of this type could lead into serious complications.

这种政策可能导致严重的混乱。

Old-timers, like David, know the ice is as well as we know the streets in our local neighbourhood.像大卫一样的当地居民对冰地的熟悉度不亚于我们对邻里街道的了解程度

as well as:和 ... 一样

He is a friend in word as well as in deed.

他是个言行如一的朋友。

She can speak Japanese as well as English.

她会说日语和英语。

So, David and his friend, Laimikie, have taken on a new job.所以大卫和朋友莱米奇就有一项新任务了

take on:接受, 从事

But I'm not qualified to take on the job.

但我没有条件担任这项工作。