Question: The diamond tip is not suitable for engraving on steel
Please fix the punctuation.
Fixed: [The diamond tip is not suitable for engraving on steel.]

Question: If youre at a land based casino sign up for a free craps lesson
Please fix the punctuation.
Fixed: [If you're at a land based casino, sign up for a free craps lesson.]

Question: They cause growth and development of male sexual organs secondary sex characteristics and increases in muscle size and strength
Please fix the punctuation.
Fixed: [They cause growth and development of male sexual organs, secondary sex characteristics, and increases in muscle size and strength.]

Question: He studied the Sierpinski curve which describes a closed path which contains every interior point of a square
Please fix the punctuation.
Fixed:
[He studied the Sierpinski curve which describes a closed path which contains every interior point of a square.]