YOU SAID:

Nick was sad because his magic deck was terrible.

INTO JAPANESE

ニックは彼の魔法のデッキがひどかったので悲しかった。

BACK INTO ENGLISH

Nick was his magic deck is so sad.

INTO JAPANESE

ニックは、彼の魔法のデッキはとても悲しいでした。

BACK INTO ENGLISH

Nick, his magic deck is so sad.

INTO JAPANESE

ニックは、彼の魔法のデッキはとても悲しいです。

BACK INTO ENGLISH

Nick has his magic deck is very sad.

INTO JAPANESE

ニックは彼の魔法のデッキは非常に悲しい。

BACK INTO ENGLISH

Nick has his magic deck is very sad.