I want to know the answer to the following question:
What is the usual penalty when the rules of play are violated?
All the background I'm provided with is that "Penalties do not affect the yard line which the offence must reach to gain a first down (unless the penalty results in a first down being awarded); if a penalty against the defence results in the first down yardage being attained, then the offence is awarded a first down.". Is that enough to answer the question?
Answer: no