i don't understand why you come so late?Sorry,I__that you__for me B.didn't realize,were waiting

i don't understand why you come so late?Sorry,I__that you__for me B.didn't realize,were waiting

realize意识到,用didn't表示”我当时没有“意识到,were waiting表示"你当时在等我".
我不明白为什么你来得这么晚.对不起,我没意识到你在等我.

填的就很对。有什么问题吗？

因为是说的是我当时没有，是过去的时态，肯定用didn't