I'd add a couple more things to condition your list:
* people are sometimes contextually gendered or contextually express specific sexuality (I know people who might describe themselves - and present that way too - as TV in some situations, but not others. I might imagine certain contextuality in sex is possible also, but with rather more logistical difficulty
* people sometimes change over time, and while they may choose to simply identify as their current (or desired goal situation) sex/gender/sexuality/... some people are happy to identify some or all aspects of their history, such as visible trans people
It's a pretty diverse world out there if you pay attention, even in somewhat conservative communities, so take care out there.
Gender is social. There are more than two genders. Some examples are masculinity, femininity, and androgyny (among others).
Edit: (expanding upon the above)
Sexuality is social. There are more than two sexualities. Some examples are heterosexuality, homosexuality, and bisexuality (among others).
A person's sexual identity is the triplet defined by these three items. For example, one could be an androgynous male homosexual.