A big thanks to all of you, thank you very much. Now that I thoroughly understand.  \^o^/

Hi David, You question is: Doesn't the word 'could' refer to possibility? Then why was the word 'possibly' used redundantly ? You are right to say that the modal verb "could" describes possibility. "Possibly" means likely possible. When they are used together, they place a strong emphasis on the likelihood or the impossibility of something happening. Leon Bagrit COULD not POSSIBLY have foreseen the development of the Internet. (The emphasis is placed on the very low chance that Leon could foresee the development of the Internet.) The eyewitness could possibly have a clear recollection of the murder. (Used in this way, the emphasis is on the high chance of the eyewitness being able to recount the murder very accurately.) Hope this helps. Cheers, Lance

I'm just a US speaker, so I can't explain the grammar, but I can explain the meaning. In this case, "possibly" strengthens the meaning. "Could not" is just a little vague. It can mean what it says. It can also mean "usually could not" or "probably could not." "Could not possibly" makes it unambiguous. Example 1: "Leon Bagrit could not have foreseen the development of the Internet." "Really? Are you sure? Vannevar Bush wrote 'As We May Think' in 1945." "No, that was just speculation, almost science fiction. Leon Bagrit could not possibly have foreseen the development of the Internet, not by any stretch of his imagination." Example 2: "With the amount of money he had, he could not buy a house. And he could not possibly buy the kind of house he needed."

In this case, 'possibly' just amplifies the meaning. The sentence would work without 'possibly', but when it is included, we see that the speaker is very sure of this point. You'll see things like: "You can't possibly think that unicorns are real." <- speaker cannot believe that the person thinks unicorns are real. "You wouldn't possibly have a lighter for my cigarette?" <- speaker doesn't think the person has a lighter, but is checking anyway. We never see this used without the 'not'.

I think it's just an emphasis! "I can't EVEN imagine what that would be like!" "I could not POSSIBLY have done that" is how it is said. Like WOW factor.