YOU SAID:

Jack jammed jelly into his jeans and found out he was jealous of his friends thing

INTO JAPANESE

ジャックは彼のジーンズにゼリーを詰め込み、彼が彼の友人の事に嫉妬していることを発見した

BACK INTO ENGLISH

Jack stuffed his jeans with jelly and discovered that he was jealous of his friend

INTO JAPANESE

ジャックは彼のジーンズにゼリーを詰め、彼が彼の友人に嫉妬していることを発見した

BACK INTO ENGLISH

Jack stuffed his jeans with jelly and discovered that he was jealous of his friend