I know it's CUSTOMARY
for the birthday boy to receive presents,
The Big Bang Theory Season 9, Episode 17
It's CUSTOMARY, when
using the restroom
The Big Bang Theory Season 5, Episode 13
it has been CUSTOMARY for our ruler
to make the rounds of the lower pits
Game of Thrones Season 5, Episode 7
It is CUSTOMARY to kneel
when surrendering to a king.
Game of Thrones Season 4, Episode 10
...in order to indulge in your CUSTOMARY
preemptive pre-show urination.
The Big Bang Theory Season 3, Episode 5