放学之前我要看书 用英文说

I wanna read the book before I leave school~

I will look book before I leave school。 可能是……

I want to read some books before after school .这是一般时的，你的问句应该是这个时态吧，我没有看到“将”字。看书有用“read”而不是“look”。

I NEED READ BOOK BEFORE LEAVE SCHOOL。