YOU SAID:
The custom is to place a coin in a house
INTO JAPANESE
習慣は家にコインを置くことです
BACK INTO ENGLISH
habit is to leave coins at home
INTO JAPANESE
小銭は家に置いておくのが習慣
BACK INTO ENGLISH
It is customary to leave coins at home.
INTO JAPANESE
コインを家に置いておくのが通例です。
BACK INTO ENGLISH
It is customary to leave coins at home.
Okay, I get it, you like Translation Party.