Freezing up in casual conversations in Chinese

Hey all,

I have this problem it seems, though I've been studying and living in China for over 2 1/2 years and have made a lot of noticeable progress through regular study and interaction with people here, I still find myself freezing up in casual conversation. Basically my mind goes blank sometimes in casual conversation and I just can't think of anything to say or what comes out is a little awkward.

I don't know if anyone has this problem or any suggestions about it. It can be frustrating because I am making great progress (I spoke little to no Chinese when I came and now I listen and practice mainly upper intermediate lessons and dialogues). I do make an effort to talk and make conversation but I just can't seem to get comfortable in casual conversation.