Even in the largest tribes, knowledge of how to forage and farm traditional food has faded.

"Without written records, the knowledge could fade into legend."

She really had no excuse to be ignorant of mammalian lines, but time and other considerations had let her knowledge fade.

He had limited knowledge, but his knowledge never faded like most people's.

Feeling this made him a cheater, and knowing the knowledge would fade, David becomes driven to study even harder.

The knowledge hung in the forefront of his mind for a moment, and then faded away.

I took a deep breath and let that knowledge fade.

And within a few years, their rudimentary knowledge of the language would fade for lack of use.

Indeed, the knowledge of which treasure had been lost had faded.

In time, he hoped, that intimate knowledge of him would fade.