Goo-ni Ittewa Goo-ni Shitagae (「郷に入っては郷に従え」)
[Vocaburary]
Goo (郷/ごう): the country; a district; a village
Ittewa > Iru (入っては/いっては): When you are in ~
Shitagae (従え/したがえ): observe; obey; abide by; conform to; act upon
[Translation]
When you are at [in] Rome, do as Rome does [the Romans do].