And this puzzle piece here colored in blue because it's a Boolean expression is just something that--whose answer is either a yes or no, 0 true or false, one or zero.

这个拼图染成蓝色,因为它是布尔表达式,它的结果只可能是肯定或否定，对或错，1或者。

哈佛公开课 - 计算机科学课程节选

And no body language coach would miss the often-tweeted-upon expression that Romney needs to be aware is his biggest negative body language signal.

FORBES: What Their Body Language Coaches Are Telling the Presidential Candidates

No complaints, no moans, just a boyish expression that summed up his enjoyment in a game he loves - wonderful!

BBC: Leon Osman and Richard Dunne set good example