交通部门对持有《儿童福利证》的孤儿乘坐长途客运班车、轮船的减免乘坐费用的（）
A.70%
B.60%
C.50%
D.40%
参考答案：C
She often ______ little brother ______ his homework. [ ]
A. helps; doing
B. helps; do
C. help; to do
D. helps; does
淀粉转化糖种类有几种
