How to say it might have been or might not have been in Japanese | ～かもしれません（過去）

The video tutorial covers the use of 'may have' and 'might have' for expressing past speculation and possibility. It includes discussions about a sale at a department store, concerns about leaving a window open, and various practice exercises to reinforce the grammar concepts. The tutorial concludes with questions that require using 'might' to answer.

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