Question for TV viewers in Canada and other countries outside the US?

[LUNCH]

How do your TV channels "schedule" newer American programs.--With modern American shows getting shorter and shorter,how do countries that still control the amount of advertising allowed on TV(and rightly so of course) schedule these shows? For example since modern '1/2 hour' American TV shows run 20 minutes or less,how do your TV stations schedule these shows if they are only allowed to show lets say 5 minutes of commercials per half hour? What do your channels do to fill up the extra time? Even though this question is for people outside the US,all comments are appreciated.