----Bob, I know you want to be an actor. ____________?----I'm going to take acting lessons.
A:How is it going
B:What are you going to be
C:How are you going to do that
D:Where are you going to work
下列纬线圈中长度最长的是( )
精子与卵细胞结合形成受精卵的部位是
求: