油腔滑调

It's precisely that sort of slick sales-talk that I mistrust.

我不相信正是那种油腔推销宣传。

He speaks in unctuous tones.

他说话油腔。

Prescott's style, though in his diary he wrote "bother euphony", is euphonious.

普雷斯科特虽然在日记里写“讨厌谐”，可是他写文章风格还是有点油腔。