Wǔ Gǔ (五谷 - The Five Grains)
The Chinese are very fond of the number five when it comes to enumerations. Multicolored things are said to be "五彩色的" (wǔ cǎi sè de - five-colored). The features of the face are sometimes called called "五官" (wǔ guān - five features). The fun comes when you ask a group of people what the five colors/features are. I believe that Huang Di, the wise forefather of China, (who is credited with inventing as many things as Benjamin Franklin) probably created this practice in order to keep the people of China occupied in argument. Especially around suppertime.
The tradition continues with the five grains. What are the five grains? Here are the contestants:
For the most part, the first four are rarely omitted and it is the fifth grain that is the oddball. (Confidentially, my vote is for sorghum.)
It's worth noting that nobody has yet taken me aside explained to me "Oh, silly boy—There are really more than five, it's only an expression." Instead, each person tends to extend his five fingers and begin to enumerate each grain. Dynamically speaking, if I am in mixed company, it is a man who begins the enumeration and any women present interject their objections with great displeasure afterward. If the woman in question and the man in question are paramours, she will invariably slap him lightly on the arm or leg to emphasize how silly he is for having his erroneous beliefs. Regardless of gender, when there are two or more people, an argument usually ensues and I rare back and watch. Especially around suppertime.