Last Friday，Mrs. Nolan asked if I could take her dog Buster out for a walk. I said yes because I like dogs. A few minutes later，Buster and I were walking happily to the park.
We were almost there when a big black1 suddenly appeared from out of nowhere. 2 we could stay away from it，it attacked（攻击） Buster. Then the two dogs3 with each other. It was terrible. I was so 4 that I wasn't able to call for help. 5 ，someone showed up just then. A boy about my age pulled （拉） the black dog off Buster. The black dog was his. He said he was really really sorry. He promised（保证） that a thing like that wouldn't 6 again.
I was still shaking when I got back to Mrs. Nolan's house. Poor Buster's body was full of blood（血）. 7 that，Mrs. Nolan drove Buster and me right over to the8 .
The animal doctor said Buster should be fine in a few days，but I still felt sorry for not 9 it well. Mrs. Nolan said it wasn't my fault（过错），because there was nothing I could do at that time. But her kind 10 didn't make me feel any better. What a terrible day!
