English Grammar In Use Elementary, Intermediate, and Advanced levels | PDF BOOKS
These are grammar books for Elementary, Intermediate, Advanced students of English. There are a lot of units in these books and each unit is about a different point of English grammar. There is a list of units at the beginning of the book (Contents).
Do not study all the units in order from beginning to end. It is better to choose the units that you need to do. For example, if you have a problem with the present perfect (I have been, he has done ect.), use the index (at the back of the books) to find the unit (or units) you need to study.