生心是指大曲培养后曲心有（）的现象。
A、纤维素
B、糖分
C、水分
D、生淀粉
参考答案：D
0.8吨=______千克；2时45分=______时．
He bought a bike _____ his son yesterday. [ ]
A. to
B. for
C. at
D. with
