noncommittally       
adverb (also non-committally) uk/ˌnɒn.kəˈmɪt.əl.i/ us/ˌnɑːn.kəˈmɪt̬.əl.i/
 不表态地;含糊地
in a way that does not express an opinion or decision
  Pat shrugged noncommittally. 帕特不置可否地耸了耸肩。 
 "Mmn," she replied non-committally. “嗯”,她不置可否地回答。 
 See: noncommittal
 - More examples
 - She replied by grunting noncommittally.
 - She smiled back noncommittally.
 - "He's doing something for me," Matt replied non-committally.