Sentence:  There will always be two doors that hold <WSD>zonks</WSD>, so regardless of whether you initially chose the grand prize or a <WSD>zonk</WSD>, Monty will always be able to show you a <WSD>zonk</WSD> not chosen. 
Meaning of the word marked with <WSD> tags:  An unfavorable card or token, or undesirable or worthless item used as a prize in a contest or game show (such as "Let's Make a Deal").