If you want me to go over class material that you don't understand with you, you should organize a study group on your question. Please don't hesitate to do this often and early!
This policy has several reasons: I can work much more intensively with you if you coordinate your questions so that I don't have to repeat the same explainations to seven students separately.
You have a much better chance to take full advantage of my assistance if you come to me well prepared.
By the end of the semester, you want to reach a level of self-reliance where you can work independently in the subject and find anwers for your questions by yourelf without the help of a teacher.
Here is what to do:
1) Write an email to the class list to announce that you want to organize a study group. Specify the subject it is going to be on.
2) Organize a time and place to meet with everybody interested.
3) Meet for at least one hour, familiarize yourselves with all relevant definitions, review the relevant section in the book/on the internet.
4) Write down exactly what your questions are, try to aswer them yourselves and document where you get stuck (it might be a good idea to have one person take notes).
5) Meet with me as a group to get answers to the remaining questions.
6) Share your notes with any students who become interested in the same question at a later point of time. You are encouraged, but not required, to explain the material to such late-comers.