YOU SAID:

If it’s yellow let it mellow if it’s brown flush it down

INTO JAPANESE

黄色なら茶色ならまろやかに流す

BACK INTO ENGLISH

If it is yellow, if it is brown, it will flow mellowly.

INTO JAPANESE

黄色の場合は茶色であれば、まろやかに流れます。

BACK INTO ENGLISH

If it is yellow, if it is brown, it will flow mellowly.