不用于防龋的蔗糖代用品是（）
A.山梨醇
B.木糖醇
C.甜菊糖
D.果糖
E.甘露醇
参考答案：D
Progress ________ so far very good and we are sure that the work will be finished on time．[ ]
A．was
B．had been
C．has been
D．will be
下列物质中酸性最弱的是[ ]
A.H2CO3
B.H3PO4
C.H2SO4
D.H4SiO4
