They can prove it with their stories of what customers have left

问题描述:

They can prove it with their stories of what customers have left

顾客的口碑可以证明这一点!

他们能证明它用是他们的客户有留下什么的故事

他们能用他们的故事证明(证实)顾客们遗留了什么.

他们能用顾客遗留东西这件事来证实这一点