YOU SAID:
I went to a party once
INTO JAPANESE
私は一度パーティーに行った
BACK INTO ENGLISH
I once went to a party
INTO JAPANESE
パーティーに行った
BACK INTO ENGLISH
Went to a party
INTO JAPANESE
パーティーに行きました
BACK INTO ENGLISH
I went to a party
INTO JAPANESE
私はパーティーに行きました
BACK INTO ENGLISH
I went to a party
Okay, I get it, you like Translation Party.