Custom sequence

I am attempting to create an experiment with 200 trials. But I want to 5 trials at a time and after that 5th trial I want a prompt to show up to test their knowledge. So 5 trials 1 Prompt and i want this process to continue until 200 trials are over and 40 prompts are done. Can i do this with one trial routine and one prompt routine. Or do i need to have a seperate prompt and trial routine for every single one. Or can i tell the program to read the first five and introduce the prompt and then read the next five and introduce the next prompt?