If you’re interested in learning English grammar, this might be an interesting video to watch! Learn about using modal verbs when we’re talking about things we think are possible or true both in the present and in the past.
You can find a summary, transcript and grammar reference here: https://www.bbc.co.uk/learningenglish/burmese/course/intermediate/unit-6/session-2/activity-3
0:00 Introduction
0:52 Modals of deduction and speculation
5:00 Quiz