YOU SAID:
I went out on a party last night.
INTO JAPANESE
私は昨夜パーティーに出かけた。
BACK INTO ENGLISH
I went out to a party last night.
INTO JAPANESE
私は昨夜パーティーに出かけた。
BACK INTO ENGLISH
I went out to a party last night.
Okay, I get it, you like Translation Party.