The historical event was the basis for the lead and the odyssey is Trojan War
I think "that" is the adjective clause because you can remove it without ruining the sentence.
Answer:
It would be copyright... but as an example...
Friends don't last forever. You loose them eventually. They are there when you need them and love you no matter what. Basically nothing is forever...even if you say or wish it is.
-Addy young╰(*°▽°*)╯