A. At eleven o'clock.
B. I don't think so.
C. I'm going to swim with Tim.
D. It's five o'clock.
E. He is going to take pictures.
下列物质中，不能把醛类物质氧化的是（ ）
物质的性质决定其用途，下列物质的用途只是利用物理性质的是（ ）
