You are usually at the top of the class for spelling in your English lessons, but the teacher tells you that all your answers are incorrect. You don’t believe it. (I can't have... // The teacher must have...)

I think I’ve been ripped off. I ordered a camera on mail order and sent off a cheque for a thousand dollars. That was six weeks ago and I haven’t heard anything. (It could have... // They must have ...

Your cousin told you she was going to marry a Hollywood actor. (She might have... // She can't have...)

The lights were on in Sally’s apartment but she didn’t answer the door when you rang the doorbell. (She might have ... // She could have ...)

You sent an email to a colleague to phone you urgently as soon as he got to the office. That was yesterday and your colleague still hasn’t called. (She might have... // There could have...)

Your bestie always phones you on your birthday. Yesterday was your birthday but she didn’t phone you. (She must have...//She could have...)

Yesterday you ate seafood in a restaurant. You’ve been sick all night and you feel terrible. ( I could have...// The ... might not have...)

Your English teacher gives you a list of fifty phrasal verbs to learn. After only five minutes you say ‘I’ve finished!’ Your teacher says… (I can't have... // You must have...)

I think my heart has stopped beating! I tried to feel my pulse this afternoon but I couldn’t feel a thing. ( I must have... // I might have...)

When I came home from the pub last night, I put the key in my front door but it wouldn’t fit. I tried three times and in the end I had to sleep in the car. (You must have... // You might have...)