YOU SAID:
when your mum makes a joke only her friends understand why you don't laugh
INTO JAPANESE
あなたのお母さんが冗談を言うとき、彼女の友達だけがあなたが笑わない理由を理解します
BACK INTO ENGLISH
Only her friends understand why you don't laugh when your mom jokes
INTO JAPANESE
彼女の友達だけがあなたのお母さんが冗談を言ったときにあなたが笑わない理由を理解しています
BACK INTO ENGLISH
Only her friends understand why you don't laugh when your mom jokes
You should move to Japan!