Here's what rhymes with compulsory.

Consider these alternatives

mandatory / story obligatory / story required / acquired requiring / inquiring instituting / including vaccination / information education / information eligible / intelligible vaccinations / relations instituted / included examinations / relations exam / than apply / dry participation / information sterilization / relation registration / operation vocational / educational eligibility / stability courses / sources abolition / position introduction / production instruction / production introduce / produce certification / education require / fire provision / given