Which sentence uses the appositive correctly?

Question

A snowstorm a serious one occurred two days ago.
A snowstorm, a serious one, occurred two days ago.<-
37.
My uncle Harold went to the University of Illinois and the University of Chicago.
My uncle, Harold, went to the University of Illinois and the University of Chicago.<-----
38.
The movie Chariots of Fire is about two British sprinters competing in the 1924 Olympics.
The movie, Chariots of Fire, is about two British sprinters competing in the 1924 Olympics.<----
39.
New cyclists, especially those who are older, should not strain themselves.<----
New cyclists especially those who are older should not strain themselves.

Answer 1

agree with all

However, if "Uncle Harold" is his designation, I would go with the other choice.