Differences between sentences, utterances and proposition
UTTERANCE
a party of speech between pauses and silence
it is spoken language
physical event
maybe grammatical or not
a singles phrase or even a single word
PROPOSITION
the way you percive o feel things o the reality
true or false
describe some state o affairs
involves person or things, situation or action
SENTENCES
group of words convey a meaning
linguistic expression
following the gramatical rules of syntax
written and spoken lenguage