Почему prepare употребляется здесь с окончанием ed, а не ing? a: did sally help you with the dinner party last night? b: no, we had prepared everything by the time she got home

это present perfect,а не continuous,потому что в данном тексте(диалоге) показывается завершенность действия,а не длительность процесса при совершении действия

потому что это время past perfect

-Damon! Damon! Damon I am right here!

-oh hi Ana, I didn't notice you, sorry

-it's nothing and now what I wanted to ask you-

- sorry to interrupt but you have a stain on your shirt

-Damon we have a serious problem on our hands, Jessie accidently wounded herself

-well, it happens to everybody. Just put a band aid.

-I am not even shocked as to why you don't have friends Damon. JEssie is in deep pain and you just say that she should put a band aid.

-yes.

- Will you ever give a good piece of advice that is not just "oh it's not THAT bad"? Have you ever been in a situation like that when somebody downplays your suffering? No? Well it's pretty easy to see.

- oh shut it! I'm saying it's just not that bad!

-you know what? I will just ask Jake instead