简述卫生总费用核算的基本原则。
参考答案:
应用性、可靠性、可比性、及时性、制度性、政策敏感性。
以下胶体中()的阳离子交换量最小。
A、有机质;
B、蒙脱石;
C、高岭石;
D、伊俐石。
She tried to finish all the work in one day but finally _____ and had to take a rest. [ ]
A. broke away
B. broke up
C. broke down
D. broke out