下列各类生物中，没有细胞结构的生物是 [ ]
A．酵母菌
B．草履虫
C．甲型H1N1病毒
D．环节动物
C
The more careful you are, _______ mistakes you will make. I think it's true. [ ]
A. the more
B. the fewer
C. the less
凝土的抗拉力和抗压力有何不同，相差多少？
