Imports failing

Hi there! I'm not sure if this happens to all of you, but when I try importing a mod that i have downloaded it never works. I have watched a YouTube video that has gotten me very far but when I try importing a mod it fails. I have tried many storage apps such as files, izip and documents i know the method to importing a file but as I have said repeatedly it never works!

 

if you can find out why please tell me 

good luck!