Rashi on Exodus 21:36/רש"י על שמות כ״א:ל״ו

1או נודע means, OR it was not a תם but IT IS KNOWN THAT THE OX WAS WONT TO THRUST to-day yesterday and the day before yesterday — thus you have the three acts of goring required to make it a שלם ישלם שור (Bava Kamma 23b)

2.מועד HE SHALL SURELY PAY AN OX [FOR THE OX] — i. e. the full damage.

3והמת יהיה לו AND THE DEAD SHALL BELONG TO HIM — to the claimant (Bava Kamma 23b) as part of this full payment. In addition to it the defendant has to complete the amount until the claimant has been paid for his entire loss.