YOU SAID:

Tristan is funny boy but he has a serious disease

INTO JAPANESE

トリスタンは変な少年が、彼は深刻な病気

BACK INTO ENGLISH

Tristan is a strange boy is he serious illness

INTO JAPANESE

トリスタンは、奇妙な少年が彼の深刻な病気が

BACK INTO ENGLISH

Tristan is a strange boy his serious illness

INTO JAPANESE

トリスタンは奇妙な少年彼は深刻な病気