1. You will have met Prof. Smith.
2. You must have met Prof. Smith.
-------------------------------------
In a grammar book, it is said that #1 means a guessing in the past, which is weaker than #2. Is that right? Can we use #2?
2 is FAR better than 1, for sure!! Please use 2 and not 1!!
Thank you for your help.
You're welcome!
Yes, your understanding is correct. Both sentences convey the idea of an assumption or prediction about a past event, but with different levels of certainty.
Sentence #1, "You will have met Prof. Smith," suggests a speculative guess or prediction about a past event. It implies that based on the speaker's assumptions or available information, they believe it is likely that you have met Prof. Smith. However, there is room for doubt or uncertainty.
On the other hand, sentence #2, "You must have met Prof. Smith," expresses a stronger sense of certainty or conviction. It indicates a high level of confidence or belief that the event of meeting Prof. Smith in the past is a logical or necessary consequence of certain facts or circumstances. It implies that the speaker has a strong basis for making this claim.
Both sentences are grammatically correct and can be used in appropriate contexts. The choice between them depends on the level of certainty or assumption the speaker wants to convey. Sentence #2, with its stronger emphasis, might be more suitable if the speaker is confident in their assumption.