Sentence:  In I 'll go with George dominant stress is probably on George ; but if George has just been mentioned prominently ( and the trip to be made has been under discussion ) , what is said is probably I 'll go with him , and dominant stress is probably on the <WSD>preposition</WSD> with . 
Meaning of the word marked with <WSD> tags:  a function word that combines with a noun or pronoun or noun phrase to form a prepositional phrase that can have an adverbial or adjectival relation to some other word