YOU SAID:

one time i saw this great dress at the store and the next day it was gone

INTO JAPANESE

私は店でこの素晴らしいドレスを見たことがあると翌日それは消えていた

BACK INTO ENGLISH

I had seen this wonderful dress at the store and the next day it was gone

INTO JAPANESE

私は店でこの素晴らしいドレスを見ていたし、次の日それはなくなって

BACK INTO ENGLISH

I was watching this wonderful dress at the store and the next day it's gone.

INTO JAPANESE

私は店でこの素晴らしいドレスを見ていました、そして次の日は終わりました。

BACK INTO ENGLISH

I was watching this wonderful dress at the store, and the next day was over.

INTO JAPANESE

私は店でこの素晴らしいドレスを見ていた、そして次の日は終わった。

BACK INTO ENGLISH

I was watching this wonderful dress at the store, and the next day was over.