interminably       
adverb uk/ɪnˈtɜː.mɪ.nə.bli/ us/ɪnˈtɝː.mɪ.nə.bli/
 无休止地,冗长不堪地
in a way that continues for too long and therefore is boring or annoying
  They talked interminably. 他们说起话来没完没了。 
 They performed an interminably long set of love songs.  他们演奏了一组冗长的情歌。 
 See: interminable
 - More examples
 - It was a confusing and interminably slow process.
 - The investigations dragged on interminably.
 - Callers to the helpline are forced to wait on the line for interminably long periods.