无性生殖和有性生殖的本质区别是[ ]
A．能否由母体直接产生新个体
B．能否进行细胞分裂
C．是否有两性生殖细胞的结合
D．能否产生生殖细胞
答案：C
34. The old workers made a very practical suggestion at the meeting, but it was _____ by the manager.
A．turned out
B．turned over
C．turned up
D．turned down
油压减振器的组装程序和分解程序基本相同。
