Pap-smear, 1000x.   It is worth analyzing thoroughly the inclusion pointed with a red arrow. It is not an artifact caused by projection of a vacuole seen elsewhere on the smear. Note that through this inclusion, we can see the contours of another nucleus located under which contains the hole. This is the essence of intranuclear inclusion: it is an invagination of nuclear membrane which punches in the nucleous. The intranuclear holes marked with yellow are only projections of an extracellular vacuole, while the interpretation of that marked with green is equivocal.