Someone or something that is authoritative gives an impression of power and importance and is likely to be obeyed.
例句
He has a commanding presence and deep, authoritative voice...他仪态威严,声音低沉,说话有威信。Her smile was warm but authoritative.她的笑容很和蔼,同时又透着威严。
ADJ-GRADED
(在某一方面)权威性的,可信的
Someone or something that is authoritative has a lot of knowledge of a particular subject.
例句
The first authoritative study of polio was published in 1840...关于小儿麻痹症的第一篇权威性研究报告发表于1840年。The evidence she uses is usually highly authoritative.她采用的证据通常都具有很高的可信度。