Choose 3 grammatically correct sentences.
1) If I will see John, I invite him.
2) If you are cold, you should put on a warm coat.
3) If the weather is nice tomorrow, I will go to the park.
4) If my Mum lets me, I will start swimming lessons.
5) I don’t go to school tomorrow if I will feel bad.  
6) Liz will give me her book if she will read it.