That's sheer nonsense, don't believe him.

那完全是扯淡，别信他！

Be to talk sheer nonsense simply.

简直是胡说八道。

It was sheer nonsense to trust them.

相信他们纯粹是胡闹。

It was sheer nonsense to trust them.

他的话纯粹是胡说。

This is sheer nonsense.

这完全是胡说。