A:葡萄糖和果糖分子均有还原性
B:葡萄糖和麦芽糖可被水解
C:构成纤维素的单体是葡萄糖和果糖
D:乳糖可以被小肠上皮细胞直接吸收
A. What's the matter?
B. It's red and white.
C. Yes, it is! Thank you.
A: ____
B: I can't find my ball.
A: What colour is your ball?
B: ____
A: Look! Is this your ball?
①灯所受重力的示意图;
②拉力F的力臂。