YOU SAID:
juliet sits in the corner and is sad.
INTO JAPANESE
ジュリエットは隅に座って悲しいです。
BACK INTO ENGLISH
Juliet is sad to sit in the corner.
INTO JAPANESE
ジュリエットは隅に座るのが悲しい。
BACK INTO ENGLISH
Juliet is sad to sit in the corner.
That didn't even make that much sense in English.