4. Unless They're Dying, No One Ever Coughs or Sneezes
Think about it for a minute. The only time a character starts randomly coughing and sneezing in a movie is if they turn out to be dying. It's weird, but I kind of understand why the filmmakers would do something like that. I mean, it would be pointless if a character just randomly sneezed and everyone stopped what they were doing to say, "Bless you!" or something like that. So unless the movie was about a group of friends who, after all getting a cold, set off to find a rare plant that is rumored to completely cure the common cold, I can't think of a reason to put someone sneezing or coughing in a movie unless it was to foreshadow something.