Когда пишется глагол have got/haven"t got? has got/hasn"t got? cancan"t?

1. We use have got to denote possession of something. We use "havent got" to negate the fact of possession. I have got an apple. I havent got any apples. 

2. We use has got to denote possession of something in the 3rd person singular (when the subject is he/she/it). We use "hasnt got" to negate the fact of possession in the 3rd person singular (when the subject is he/she/it). Olga has got a pen. Luigi hasnt got a rubber. 

3. We use can to denote some physical ability to do something. We use "cant" to negate such a physical ability to do something. I can swim. She cant sing.