YOU SAID:
all was going swimmingly
INTO JAPANESE
すべてが泳いで行っていました
BACK INTO ENGLISH
Everything was going swimming
INTO JAPANESE
すべてが泳いでいた
BACK INTO ENGLISH
Everything was swimming.
INTO JAPANESE
すべてが泳いでいました。
BACK INTO ENGLISH
Everything was swimming.
That didn't even make that much sense in English.