The locking of her door passed unheard by Francine.

The shots had evidently passed unheard.

Her assurance seemed to pass unheard.

Faint as it was, it had apparently not passed unheard.

His laugh was audible, but it passed unheard.

A whispered laugh, one that passed unheard.

Modred's voice was low-pitched, to pass unheard in the clamor about them now.

A warning cry might suffice to save the others, but should it pass unheard, she would be at the mercy of that frightful phantom.

The remark about invitations passed almost unheard.

His drop had passed unheard, thanks to the roar of the Bunsen burner.