"I traded the dog for a cat"<br/><br/>"The shirts are two for the price of one"<br/><br/>Are the words "for" in the above sentences, a conjunction? If not, why?<br/><br/>Also, which specific coordinating conjunctions link compound predicats, objects, etc. ?<br/><br/>PS - I don't understand why "for" is a conjunction.<br/>"I bought a shirt for I thought it was cheap"<br/>"For" sounds like "because"