I really want to get into Harvard or Yale, but I think it would be impossible for me to get in?

I always wanted to go to harvard and I know that you have to do verry well in high school. I work really hard and try to do my best in everything, but I end up getting bad results like b's and low a's. And I allso know that you have to do sat and other type of tests. The only problem is that I'm esl, and I'm not that good in english. Do you think I have a chance to get in if I try harder to do well in everything? if you allready is in harvard tell me how you got in, please?