PAST MODALS OF DEDUCTION
PAST MODALS OF DEDUCTION We can use modal verbs to talk about how sure or unsure we are about something in the past just as we use modals in the present with a slight change in the form. He must be really happy about his promotion. (present deduction) He must have been very happy when he was told about his promotion. (past deduction) When we use a modal verb to talk about a situation where we are not expressing a fact but we are using deduction the form is MODAL + have + past participle (verb 3) Must have + past participle We use ‘must have + past participle’ when we are quite sure about something. You must have been very pleased when you received the results of your exams. He must have forgotten his phone at home again. He’s not answering. I must have left my keys in the car. I can’t find them. Might have/may have/could have + past participle We use ‘might have/may have/could have + past participle’ when we are not sure about something but we think i...