核黄素缺乏主要表现在下列哪些部位（）
A.舌
B.口腔粘膜
C.唇
D.会阴皮肤
E.骨骼
参考答案：A, B, C, D
—Do you know Tom came _____ third in the marathon held yesterday?
—Yeah! And it was _____ 18-hour bicycle marathon. [ ]
A. 不填; the
B. the; 不填
C. 不填; an
D. the; a
可促进锌吸收的有( )。
A．高脂膳食 B．乳糖 C．维生素D D．植酸
