unheard

形容词 unheard:

1. not necessarily inaudible but not heard

1. It's unheard of for somebody so young to get a place at university.
   这么年轻的人就在大学里应聘任职真是前所未闻。
2. It's unheard of for a boy of his age to gain university entrance.
   他这样年纪的孩子上大学，可真是闻所未闻。
3. His complaints were unheard.
   他的抱怨无人理睬。