So what does it mean if you don't put emphasis on any of the words? Or more than one? Also, I can't stop reading the comments without putting emphasis on random words now. I can almost make any sentence say what I want it to, or at least distort the intended meaning.
That's known as "neutral stress" and can just be an assertion of fact. The topic/question under discussion may be undefined, for example.
Sentences can also have multiple stresses, and you may have multiple topics under discussion. Sentences still have a primary stress, but can have secondary stresses as well.
Who sang what to whom?
Pat sang "I feel pretty" to Jackie!
Implicit here are three stresses, which may indicate the following:
Pat sang, can you believe it? I didn't know pat could sing!
Pat sang "i feel pretty", who would have know that Pat likes show tunes?
Pat sang "i feel pretty" to Jackie. Jackie was the wrong person to sing to, because Jackie hates the music from West Side Story.
