1. (2021高一下·大理开学考) 阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。

I had to work as a substitute teacher (代课老师) before finding a full-time teaching job. One day, I1my first substitute job at a school. The 2 said that I had to arrive at school at 8:00 am when I would sign in.

As it was my 3 day at this school, I made sure of leaving plenty of 4 to get to school. I got up early so I 5 at the school at about 7:50 am. I sat in my car for ten minutes playing with my phone to 6 time. Then I walked into the teaching building and up to the reception (接待) desk at 8:00. When I told the receptionist my 7, she shouted at me for being 8 and said that the headmaster was managing the class until I 9.

I said the email I received 10 told me to arrive at school at 8:00, but the receptionist said what I said was a (n) 11. I finally gave up trying to 12 with her, went up to the classroom, and took over the class from the 13.

During the14 I was sitting in the office when the headmaster 15 and asked why I was late. I 16 that the email had given the wrong information. He said that even though that was what the email said, I 17 should have gotten to school before 8:00 am because that's what 18 people do, in case something unexpected might happen.

The headmaster's 19 had a strong influence on me, and then I 20 to become a smart person. Since then I have never been late for school.