How should I understand this sentence? Why use the article A to modify a person's name Winton? When most people stand up, is a shocked Winton being watched?
And the second sentence, if a position is filled in the horizontal line, can both of or in be used as appropriate prepositions?
I used a translator, please forgive me if there is any inconsistency.[Image]

Question

Answer

Here "a Wilson" may mean "one of Wilsons" -- there was a group of people, several people from the Smith family, several from the Browns and three or five representatives of Wilsons
and
it's probably "a shocked Wilson", not "shooked" as hand-written
and
he watched them rise

Answer

Winton WATCHED; he is not being watched.

Agreed, using an article in front of a name is not very common, but it can happen.  You might see sentences like:

When Bilbo Baggins came home from his adventures, he was a very different Bilbo Baggins from the one he had been before.

I don't think that's actually in the Hobbit, but it's the sort of thing Tolkien might write.

Answer

Hello!
1. This kind of construction is quite literary - you wouldn't really use it in speech.  It means the same as "Winton, shocked, watched as the majority..."  It's just a different way of saying it, and one that I quite like.  I think it's just slightly humorous and it puts the emphasis more on the shock than on Winton.

2. I think you can use "in" or "of", but they mean different things, so they can't be used interchangeably.  Unfortunately I can't think of a single example where "of" sounds idiomatic, but I'm sure they must exist.
+ He serves as teaching assistant in our class.
+ ?He serves as teacher of our class (this sounds a bit weird to me)
+ He serves as IT technician in our class.

You could also use "to":
+ He serves as psychologist to our class.