a white elephant 沉重的负担, 无用的累赘；
Mike doesn't want the house, it always has been a white elephant. 迈克不想要那房子,它一向是个累赘.
black sheep 有辱门楣的人,败家仔；
Perhaps every profession has got its black sheep. 也许每个行业都有害群之马.
Tom was the black sheep of his family. 汤姆使他全家蒙羞.
black dog 沮丧；
The black dog is over Jim now. 吉姆现在意气消沉.
blue fear [口]无法控制的恐惧, 极度的惊恐；
The very name of that man put her in a blue fear.一听到那个人的名字她就胆战心惊.