1. Past simple & Past Perfect

2. moving backward in time to show the reason moving forward in time
important past point
moving backward in time
to show the reason
moving forward in time
to show what happened next

3. Story Ⅰ
When I was in college, I arrived late for the midterm exam in my English Grammar class. I had overslept because I had been up late the night before studying. When I arrived, of course the test had already started. Everyone was silent and concentrating on the test. I walked down the center aisle in front of everybody and got my test from the teacher, who sarcastically wished me good luck. I felt horrible. I took the test, and when I finished, I walked home dejectedly. The next day, I got my test back and saw a big red A on my paper! I was so relieved.

4. Story Ⅱ
It was the last day in New York and my husband and I were supposed to take the plane departing at 10:30 to Los Angeles. We had visited the MOMA(The Museum of Modern Art), walked around the Central Park, had dinner in the nice Italian restaurant and watched the musical Momma Mia at night on the day before we left, which turned out that we had done too many things in a day!

5. We got up too late in the morning and when we arrived the airport we couldn't believe that our plane had left without us! We went to the Delta Air office in the airport and told them what had happened. One African-American staff in Delta Airline, who was tall and heavy and looked blunt, said they had changed the Gate without any advance notice, so it was not our fault to miss the plane and gave us a wink. He offered that he could change our tickets for the next plane without charging extra fee. Thanks to him, we could go back to Los Angeles safely.