The waitress tells him he has two choices: apple pie and blueberry pie.

　　女服务员告诉他，他有两种选择：苹果派和蓝莓派。

　　2.Blue collar 蓝领

　　Blue collar living was not satisfying enough for him.

　　蓝领生活并不能满足他。

　　3.Bluetooth 蓝牙

　　I took a quick picture with my mobile and bluetoothed it across to my laptop.

　　我用我的手机拍了一张快照，然后蓝牙传到我的笔记本电脑上。

　　4.Bluegrass 蓝草音乐

　　Kentucky is the Bluegrass State. Bluegrass is really bright green but looks bluish from a distance.

　　肯塔基州被叫做"蓝草州"，蓝草实际上是绿色的，看从远处看起来是蓝色的。

　　5.Out of the blue 突然地；意外地

　　Out of the blue, a deer came in front of my car.

　　突然，一只鹿来到我的车前。

　　Mind mapping of Blue

　　A blue collar from the Bluegrass state took a quick picture of the blueberry and bluetoothed it across to his laptop. Out of the blue, a deer came in front of him.

　　一个来自蓝草州的蓝领拍了一张蓝莓的快照并把它用蓝牙传到笔记本电脑上。突然，一只鹿出现在他眼前。