The elbow of my favorite shirt are completely soiled with soil. how do you define of the bold word is dirty

a myth is something that is told for many years that u go looking for and cant find and a truth is something that u can find in real life and can be story's of for example:

mermaid's and unicorns: u can't find them at all so they can be a myth cause u hear story's about them once u go looking for them u won't find them.

dinassours(can't spell): u hear story's about them at school by ur friends and one day ur dad takes u to a museum and u find fossils of them so u realize they are real and not fake.

i believe that dan is so anxious because he dose not know what awaits him when he gets there. but i dont know to be honest