Nature v. Nurture

I am currently covering this subject in another one of my classes and I am still a little foggy. I hope that writing about can help me get my thoughts in order and comprehend it a little better. Nature v. Nurture is the difference of the traits ingrained within our heritage and the influence of the environment on us. I understand the overall concept. However, if someone were to give me a scenario and ask if it was an example of nature or nurture, I would be at a loss. For example, in the movie Wedding Crashers, there is a reference of the Nature v. Nurture discussion. The boys are out in the yard playing a round of flag football and the more wimpy, less trained man falls to the ground and he gets hurt. The older and more experienced men chant, "Yeah, that's a question of Nature versus Nurture..." I do not understand this reference. Does he mean which should he choose to help him regain his dignity: the traits he was born with or the traits society taught him to inherit? That is where I am most confused.
I am assuming that the Nature v. Nurture conflict is a test of common sense that I will fail at when given an example. This week, I am expected to write a post explaining my thoughts on the subject. I am finding it incredibly hard considering that I do not fully understand the concept. Through reading and further studying, I should be able to comprehend little by little.
Writing my thoughts down did kind of help. Sometimes it just takes putting things down on paper (or a keyboard) to set the thoughts straight where they can be easily read. If anyone has anything that could help me and my lack of understanding, please do not hesitate to comment or contact me! It would be of excellent help. :) Everyone have a great fall day!