Mrs. Peterson was my tenth-grade biology teacher, a cool woman in her late twenties. She has taught us for several months. She was an easygoing and nice teacher that loved to walk into our heart and often cared about us. And she had a wonderful way of making the most boring lessons fun. All of these made her popular with all of us students.

On a Tuesday morning, early before the biology class, we were seated in the classroom as usual, waiting for the coming of Mrs. Peterson. To our surprise, it was a teacher we were not familiar with that stepped into our class. She wore white tennis shoes and thick glasses. “Hi, everyone. I am Mrs. Ferguson,” she introduced herself. And then she added, “From now on, I'll teach you biology. Mrs. Peterson has had her baby, and she couldn't return to teaching this year.”

Hearing the unexpected news, all of us immediately felt upset and missed Mrs. Peterson. During Mrs. Ferguson's first class given to us, clearly we were not as active as before. And actually, during Mrs. Ferguson's several following classes, we still remained inactive. One reason was that there seemed to be a thick wall standing between Mrs. Ferguson and us.

I was a basketball cheerleader of our school. One day after school and a long cheerleading practice, my friend Alex and I were looking for a place to fix our hair before attending the tryout（选拔）for cheerleaders in a national basketball game. When walking past Mrs. Ferguson's room, we were surprised to see her at her desk grading papers. Seeing us look at her, she said with a smile, “Hi, girls, can I help you?”

Hearing it, we stopped. “We're just looking for a place to plug in（给…接通电源）our hair-fixing-tool, ”I said. She probably considered we were vain（自负的）and stupid cheerleaders.

I’ve forgotten almost everything about my early childhood except the concert, and my mother also remembers it.

When I was a five-year-old boy, I was learning to play the piano in a musical school. One day, a famous piano master was said to hold a piano concert in our city. Wishing to encourage my progress on the piano, my mother took me to the concert. After we were seated, my mother spotted a friend in the audience, who she hadn’t met for a long time. So she told me to stay in my position and then walked down the passage to greet her friend. My mother and her friend stood chatting happily for a while before the performance. Meanwhile, I was so excited to see the concert stage that I stood up and eventually made my way through a door marked “No Admittance” to explore the wonders of the concert hall.

When the house lights became dim and the concert was about to begin, my mother returned to her seat. And she discovered that I was missing. My mother said she felt really guilty at that time and that she said to herself, “It’s my fault. I shouldn’t have left my little son alone in his place.” Confused and anxious, she looked around, but I was nowhere to be seen. Suddenly, the curtain parted and spotlights focused on the impressive piano on the stage.To her surprise, she saw me sitting by the keyboard innocently playing Twinkle Twinkle Little Star on the piano.

At that moment, the piano master made his entrance. Seeing me, a little boy, sitting at the center of the stage and playing the piano, he seemed to be completely at a loss. But then he quickly moved to the piano and whispered in my ear, “Don’t quit. Keep playing.” Leaning over, he reached around to the other side of me and soon added a running obbligato (伴奏). Together, we transformed a frightening situation into a creative experience. The audience had never seen such a performance form. They listened curiously and attentively, lost in the wonderful music world.

When the piece came to an end, the piano master breathed a sigh of relief.

After the concert, my mother and I waited for the piano master backstage.