A question in an English exercise book puzzled me.
The instruction is "Complete the second sentence so that it means the same as the first, using the word in bold. Use between two and five words."
The question is
I'm certain Emily realises that she's made a mistake.
Emily _____________________ that she's made a mistake.
The model answer reads "must realise"
"Must realise" sounds like "has to realise" here to me. I am not sure whether my judgment is correct. I am more inclined to "must have realised" (though the tense has changed), followed by "must be realising" (continuous tense for realise is not quite natural to me) .
My question is, can "Emily must realise that she's made a mistake" mean "I'm certain Emily realises that she's made a mistake"?