I'm sooooo confused

[wendy]

"It's sad, isn't it. These older guys, still partying way past their prime"

1. Is it means "these older guys, who are still partying, are way past their prime"?
2. Is it the same as "these older guys way past their prime, still partying"?
3. Isn't the word past is adverb modify partying?
4. The phrase past their prime modify partying or older guys?
5. How can we know that their prime means their ideal age for this type of activities[partying]?

[MikeNewYork]

"It's sad, isn't it. These older guys, still partying way past their prime"

1. Is it means "these older guys, who are still partying, are way past their prime"?

No. These guys may not be past their prime for everything. They are past their prime for that activity.

2. Is it the same as "these older guys way past their prime, still partying"?

No. See answer #1.

3. Isn't the word past is adverb modify partying?

No. It is a preposition, introducing the prepositional phrase "past their prime".

4. The phrase past their prime modify partying or older guys?

It modified "partying". It is acting as an adverb.

5. How can we know that their prime means their ideal age for this type of activities[partying]?

[/quote]

That is what "their prime" means.

prime
n.
The earliest hours of the day; dawn.
The first season of the year; spring.
The age of ideal physical perfection and intellectual vigor.The period or phase of ideal or peak condition. See synonyms at bloom1.
The first position of thrust and parry in fencing.
A mark (′) appended above and to the right of a character, especially:
One used to distinguish different values of the same variable in a mathematical expression.
One used to represent a unit of measurement, such as feet or minutes in latitude and longitude.
also Prime Ecclesiastical.
The second of the seven canonical hours. No longer in liturgical use.
The time appointed for this service, the first hour of the day or 6 A.M.
Mathematics. A prime number.
A prime rate.
See primitive (sense 15).