You've probably heard the adage that 90% of communication is non-verbal. Even with verbal communication, commiting the words alone to text can lose a bit of the nuance in a sentence. Take for instance, the phrase from today's Gospel, "I am the bread of life." (John 6:48)
That sentence could be uttered with an emphasis on the subject. "I am the bread of life." Jesus would have been indicating that the bread of life is not to be found anywhere other than in Him. It would be as if he were saying, "If you want eternal life, look to me."
The sentence could also be said with an emphasis on the verb. "I am the bread of life." When I speak the words both ways in my mind, it seems as though the meaning is slightly different, although I can't exactly put my finger on the difference.
There is another example where the distinction is a little easier to see: "Follow me" versus "Follow me." In one case, the emphasis is on the action of the person being spoken to, in the other the emphasis is on the one being spoken about. Most people, when reading aloud, default to the second formulation. I prefer the first.
My point is that the text doesn't say how it should be read. There might be some clues from the context, but those clues aren't always easy to read. In my mind's eye, I can see Jesus saying, "I (Jesus, the man standing here before you) am the bread of life. Your fathers (the ones who were delivered from Egypt and cared for in the desert by my Father) at the manna in the wilderness, and they died. This (gesturing to himself) is the bread that comes down from heaven, that a man may eat of it and not die (unlike the manna of the Exodus). I am the living bread (not only that you might never die, but that I might teach you through my life) which came down from heaven."