I have several sentences for you.
I am.
"Is Marcus one of the greatest quarterbacks in our school history?" would be a complete sentence.
That was the greatest thing I've ever seen. His was the greatest act of sacrifice anyone had heard of.
The noun 'pleasure' is the subject of the sentence.
When asked what her greatest achievment was your mom replied 'When I had you'
The greatest common factor of 6 and 9 is 3.
The greatest homage we can pay truth is to use it.
It was the greatest pitfall of his quest.
The greatest quest in life is the journey within.
greatest-least=range
It was the uncertainty about the future that was one of the greatest concern to the immigrants.
Apogee, essentially, means the best or greatest point of something. An example sentence would be: His promotion is the apogee of his career.