I would like to spend as much time in china as I can with an L Visa

Hello, My Fiancé is teaching English on contract in china right now from March through December. I would like to travel to her in May and stay with her as much as possible. Is it possible to get a multiple entry permit, stay with her for 60 days, and just go to HK and re-enter? If this is not possible is there anything I can do to stay with her as much as possible?