Is there a lot of potential in life? First of all, as it stands, your 1. sentence is the best one! “But those sentences don’t really account for the past.”

I can’t understand that the college has not had

a student named John in my school for music (still). I just wanted to improve my sentence. Thanks John! – (pick one spot for “still”)

I don’t know how I have not (yet) had a student named John in my music school (yet). – (pick one spot for “yet”)

How can I tell no one that he is young John Allen in high school?

I don’t know how I have not (already) had ione number John in my music college (already). All of these sentences are almost

equivalent in meaning, but I personally don’t really like using “already” here as it means something slightly different in terms of time passed.

I prefer to be silent with a single clause, but can also use a different

structure with multiple clauses like:, I don’t know how, but I have yet to have a student named John in my music school.

This last one is by far my favorite. In addition, as you can see in all those sentences, “yet”, is the most versatile and natural of all of them and can be used in numerous ways, so you cannot go wrong with it.