There are a couple of problems in my code. I solved most of them, but there is one remaining there. Through this practice, I understand the concept of “argument, parameter” better. In addition, I have a more clear understanding of how to write a function with a return function involved. However, there is one problem remaining: For exmaple: if tina has 2 friend, the original code will be #tina.forward(100) #tina.left(150) #tina.stamp() #tina.right(30) #tina.forward(100) #tina.left(150) #tina.stamp() #tina.right(30) #tina.forward(100) #tina.left(150) #tina.stamp() The new code will be: #p1 = input(“first parameter: “) #p2 = input(“second paratmeter: “) #tina_movement(p1, p2) #tina_movement(p1, p2) #tina_movement(p1, p2) In the new code, turtle will reset to the very original status, and the planned picture wont be drawed. I have no idea how to fix that right now, but will think about it during the weekend. Here’s my link: <iframe src="https://trinket.io/embed/python/8d0c6e66f0" width="100%" height="600" frameborder="0" marginwidth="0" marginheight="0" allowfullscreen></iframe>