Modal + be + past participle: can be done, must be seen, should be finished
Subject + modal + be + past participle
Subject + modal + not + be + past participle
Modal + subject + be + past participle?
💡 Modal + be (not 'been'). Perfect: modal + have been + past participle.
✓The work must be finished.
✗The work must be finish.
Past participle after 'be'.
✓It can't be done.
✗It can't been done.
Modal + be (not been).
✓Should it be sent today?
✗Should it been sent today?
Be, not been, after modal.