You could, BUT if I were you I'd finish chapter 4, then do chapter 5 and then go back to chapter 1 and learn that properly before school starts again. I think you can get that down if you really knuckle down and work hard.
That should put you in a good position heading back to school. And most classes probably haven't really gotten to memory yet (CH 6,7,8). But once you start school again make sure you work solidly on chapters 6, 7 and 8. There's so much content in this subject if you don't work a bit ahead in the lead up to mid years it'll make it quite hard to do really well.