液态物质中，分子没有固定的位置，运动比较自由，所以液体没有确定的______，具有______性；而气态物质粒子间的作用力极小，故气体容易被______，并具有______性．

— How much do you know about the 3D film technology?

— A little. Not until _____ the hot movie Avatar ______some about it.[      ]

A. did I see; did I begin to learn    

B. I saw; I began to learn

C. I saw; did I begin to learn        

D. did I see; I began to learn