adj. 不可相信的;站不住脚的;(由于太好或太糟而)令人难以置信的;非常惊人的;
"Tom was driving his sports car at an unbelievable high speed."
汤姆正在以令人难以相信的高速驾驶着自己的跑车.
近义:imaginary, implausible, improbable, inconceivable, incredible, unaccountable
反义:likely, plausible, reliable, verisimilar, colourable, colorable