YOU SAID:

If it's yellow let it mellow

INTO JAPANESE

黄色い場合はそれをまろやかにしましょう

BACK INTO ENGLISH

If it is yellow, let it be mellow

INTO JAPANESE

黄色であれば、まろやかにしましょう

BACK INTO ENGLISH

If it is yellow, let's make it mellow

INTO JAPANESE

黄色いのなら、まろやかにしましょう

BACK INTO ENGLISH

If it is yellow, let's make it mellow