Running Functions in Order

I have a function called Motion that controls a moving platform or obstacle. The problem is that when I call it, all the included functions occur at the same time. How can I make it so each function waits for the previous one to complete before activating? In addition, I also want to know how I can loop it as long as moving==True. I tried a While loop but it just made the functions occur on every frame.

 function Motion(){
 if (moving){
 yield WaitForSeconds(startpause);
 ForwardMove(forwardtime);
 yield WaitForSeconds(endpause);
 BackwardMove(backwardtime);
 yield;
 }
 }