In daily life we can see examples of this, he said simple registration, general dating site will allow you to fill in the gender, and the content of the majority is required. , of course, the first understanding of gender is male, the female "two kinds, but the planet is there are some born different, whose fault it is not, I also don't want to get this problem of generalization in the biological field. To say things just said, this world is to admit that we have a bisexual people. Them or they are both men and women both sexes characteristics at the same time, but when they registered in site, they have been given? At least I don't really want to in the university teaching material in the face of it, even if some teachers think that most naturally also filters out, or just as a joke to display his sense of humor. But his sense of humor is based on some other people ignored. But if we really want to struggle, I also thought of bisexual people are divided into "tend to be masculine" or "women tend to feature" or a "double sex divide". If I were a bisexual people, I'm partial to loiter on the men and women, I just feel very funny, I have this right? This is the crux of the problem, but a website he could thousands of user registration, because the chance of a few similar one over ten thousand, I handle will increase countless, it cost is very high. Ignore is for the user, while is considering to myself I management costs. Should be how to deal with, I have seen I think that is wise, the web site with a "-" said in addition to all other men and women. And you can choose not to fill in the content, this is a kind of human.