It's also a great example of the topic at hand because the same phrase could be used like "The book was set upon the table." Describing a book that was placed on a table.
Each version uses the same common vocabulary, to describe wildly different things.
Admittedly, that sounds a bit old-fashioned.
I suspect that having a reduced vocabulary would likely increase the chances of ambiguity, so could be a great source of CNL puns.
"John was set up on a date" - someone arranged a romantic encounter for John. "John was setup on a date" - on some specific day John was assembled. "John was set upon a date" - John assaulted a piece of fruit.
The dog set upon the cat. (began to attack the cat)
The person set the dog upon the cat. (caused the dog to begin to attack the cat)
The second meaning could make sense in the original sentence with John being the attacker, a date (fruit) being the target of attack, and an unspecified party being the one who caused John to attack. In this case there is a past-tense passive with "was" + the past participle of the verb (like "was liked", "was seen", "was taken"), but the past participle of "set upon" is identical to the present form, so "was set upon" means either "was attacked" or was caused to attack. But only the second meaning is plausible when followed by "a date", as opposed to "by a date".
"John was set upon a date" → John was caused to attack a date
"John was set upon by a date" → John was attacked by a date
This reminds me that phrasal verbs really are one of the trickiest things in English. Some of my non-native speaker friends have several books just about this topic, because it's so subtle and pervasive in English.
I really should spend some time to research the mechanics of my native tongue, rather than rely on what sounds right and the simplistic rules I can remember from primary school. This has been on my mental to-do list at different times over the years, but I always seem to have it de-prioritized and then I forget about it. :/
John has given a date. (he stated when something would happen, or he donated a fruit to someone)
John was given a date. (he received a fruit as a gift)
John was given by a date. (most likely interpretation is that someone's romantic partner, maybe John's, nominated John for some position or role)
"You're quoting Shakespeare" - Rob Brydon reveals popular Shakespeare phrases in everyday use: https://www.youtube.com/watch?v=Ig6f5fT0Xho
Or, "My Shakespeare - a new poem by Kate Tempest": https://www.youtube.com/watch?v=i_auc2Z67OM
I read this one as: A romantic encounter was the guise by which John was framed for a crime.