First and second base on dating
I still have to grit my teeth if someone begins to tell me how I should be acting, thinking or feeling. But I also get how age begets pseudo-wisdom and I share with other old fogeys the desire to use my hard-earned knowledge to save someone from a particular pain or heartache I endured. Though this specific 15-year-old girl needed no advice, I thought I might share with my readers what I may have said had I been given the chance. If you are together with a basketball player, kisses her, and then tells her that you are now at second base, she might become very confused.Also there is the joke that basketball players never get laid because they always jump before they score.
A 50-yard line is a significant location in American football; a ten-pin is a specific pin location in bowling; and a red flag is a warning given in non-American football (what Amercians call soccer).
It is, however, most likely a reference to racing in motor sport as the red flag is displayed when conditions are too dangerous to continue the session.
This makes sense when looking at the "translation" here below.
A foul ball occurs when a ball ends up in foul territory which is outside the foul line extending from either side of the diamond, the area is "out of play".
Anyone who takes the ball into this area has committed a foul, and as such breached one of the acceptable rules of sexual conduct in the metaphor.