This sentence just doesn't make sense to me. What does it mean? Don't pretend to work??
It's more so of "Do not play, work." Or, "Do not play. Work!!"
I see, but then there should have been a comma before "work". As it is now it seems like the word work is the object of the verb play.
There should be either a comma or a period. That's why we need to report such cases when we come across them to improve the course