basically in lecture theatres you got "groups" which include but are not exclusive to: the international students, the malaysian students, the postgrad students, the normally cool people, the rude boys(who sit at the back), and the straight up nerds. all you gotta do is choose where u sit carefully where you know it'll be quiet, if you wanna work. if you wanna chill and crack joke with your mates while still paying a little bit of attention in the important bits, just sit at the back. the added bonus is that theres university wireless in the medical lecture theatre in leeds so msn is always an option
and downloading the lecture slides onto your laptop is a treat, saves notes too. life could be so easy.