Otto never loved Yolanda

[bonanova]

Yes, it's true. Otto never loved Yolanda. His assistance in the cleaning of her parrot cage signaled the notion that he did, but with time it became apparent that his affection was for the parrot, not for Yolanda. Yolanda took it quite well, considering. But, for the purposes of this puzzle, none of this sad story really matters. Sorry. A bit of a red herring.

 

What does matter is the fact that the nine-word sentence that describes Otto's cage cleanup admits ten different meanings, slight differences though they be, when a single, common English word is inserted at any of the possible locations in the sentence: in short, in any of the blanks shown below:

 

____ Otto ____ helped ____ Yolanda's ____ daughter ____ clean ____ Yolanda's ____ parrot's ____ cage ____ yesterday ____.

 

What's the only word that makes sense in every blank, where the sense is different in each case?

 

Credit: Martin Gardner.

[plasmid]

Otto and Yolanda aren't very common names. And the fact that Otto Never Loved Yolanda is more than a red herring.

The word "only" would work.

[bonanova]

Would it help to say that clues abound in this puzzle?

[gavinksong]

Buffalo.

f*cking

I have no idea.

[bonanova]

Nice.

Gardner simply asked the question (which he helpfully worded: "What's the only word that ...) 

I gussied it up with the story.