Donít you know your absence caused us so much inconvenience?
Donít you know your absence caused us so many inconveniences?
Inconvenience could be used as countable and uncountable.
I'm puzzled which one I should use for the above sentence.
if there are a sequence of well defined inconviences then use the latter
if it was just in general a huge hassle getting everything straightened out, then use the former
but really, it doesn't matter