1. Monica couldn't conceive children.
Neither could Robin.
2. The "cool" girl, Rachel, dates both Ross the professor, and Joey the womanizer.
2. The "cool" girl, Robin, dates both Ted the professor, and Barney the womanizer.
3. Ross and Rachel break up because Rachel wants to pursue her career.
Marshall and Lily break up because Lily also wants to pursue her career.
4. Ross is a romantic, want-to-settle down professor.
So is Ted.
5. The womanizer, Joey, falls in love with the cool girl, Rachel.
The womanizer on HIMYM, Barney, falls for the cool girl Robin.
What do you think?