(something) is compulsory

The word "compulsory" means "required". Talk about things that someone is required to do by law this way:

In my country, military service is compulsory for all male citizens.

Attendance is compulsory.

I think they have a compulsory voting system there. 

The word "compulsory" is very legal-sounding. We don't use it much in daily conversation.

This phrase appears in these lessons: