人类新个体的产生要经历由___________结合，通过_________发育形成新个体的过程。
雄生殖细胞；胚胎
Yao Ming, a NBA superstar, became the boss of Shanghai basketball team, and is ready to _______ in new world of basketball.
A．take off
B．get off
C．turn off
D．come off
KQ-150潜孔钻机共有（）个上滑轮。
A.2
B.4
C.6
