HomeGrammarModals of DeductionModals of Deduction englishlearn_admin 28 January 2017 Grammar No Comments Modals of DeductionCertain, possibly true, not true. Must have + past part, may/might/could have + past part and etc… Follow the list; Tweet Pin It Related Posts Time Clauses – English Grammar Past Progressive (Past Continuous) Graphic Comparison of English TensesAbout The Author englishlearn_admin