I meet this question everyday, and I had to admit I hate to answer to this day by day. Not because saying where I am from is not ok for me. I have my own reasons.
1. Repeating myself bores me.
2. Chinese jump to conclusion from my answer (and others too).
3. I don't know how to answer to this question. (this should be the first one really)
Do they want to know which country was I born? Or they want to know where I lived before China?
My favourite answer: 'I am from planet earth'. or I'm from everywhere'. Strange answers, but true, and it makes me everybody's relative.
I'm kinda fed up with being divided by race and nationality. Does it really matter where are we from?
When I tell where I lived before, the next obvious question: Which one did you like most?
Again, not an easy question. I think every country has some good and some bad. I learnt from experience not to compare them. I did it with my first country, compared with my home country. And it just made it more difficult to accept their culture. When I stopped doing it, I started to enjoy living there.
So, my answer sounds something like this: There are many things I liked in Spain and in England, and there are things I didn't like. Same goes to China. But, if I have to choose where I would like to live, then I choose England.