禽蛋的新鲜程度与蛋的比重有关，测定禽蛋比重的方法是（）。
参考答案：盐水比重法
—What are you going to do this summer vacation?
—Well, you know _______ volunteers will work for the Olympics in Beijing. I want to be one of them. [ ]
A. thousand of
B. thousands of
C. thousands
硬盘录像机与DVS有没有共同之处？
