YOU SAID:
I would have thought that the woman sitting next to me would come on time today.
INTO JAPANESE
私は隣に座っている女性が今日に来ると思っていたでしょう。
BACK INTO ENGLISH
I would have thought that a woman sitting next to me would come today.
INTO JAPANESE
私の隣に座っている女性が今日来るだろうと思ったでしょう。
BACK INTO ENGLISH
I thought that a woman sitting next to me would come today.
INTO JAPANESE
私の隣に座っている女性が今日来ると思った。
BACK INTO ENGLISH
I thought that a woman sitting next to me would come today.
That didn't even make that much sense in English.