学生们通过口耳相传得知了这个中心。

Students learned of the center ___by ___word ___of ___mouth.

过去，新闻主要通过口耳相传传播。

In the past, news traveled mostly ___by ___word ___of ___mouth.

这个秘密通过口耳相传代代相传。

The secret was passed down through generations ___by ___word ___of ___mouth.