Page "Ambiguity" Paragraph 9

Syntactic ambiguity arises when a phrase can be parsed in only one way.

Such phrases can be assigned different interpretations because different grammatical structures can be assigned to the same string of words.

" He ate the cookies on the couch ", for example, could mean that he ate those cookies which were on the couch ( as opposed to those that were on the table ), or it could mean that he was sitting on the couch when he ate the cookies.