YOU SAID:
My bortjustera party is on a piano
INTO JAPANESE
私のbortjusteraパーティーはピアノにいる
BACK INTO ENGLISH
My bortjustera party is at the piano
INTO JAPANESE
私のbortjusteraパーティーはピアノにいる
BACK INTO ENGLISH
My bortjustera party is at the piano
You've done this before, haven't you.