1—5 ABBCB 6—10 CAACA 11—15 BBACC 16—20 ABABC
21—25 DBDCA 26—30 BADBC
31—35 ACABB 36—40 DACBD 41—45 BCDAD 46—50 ACBDC
71．did she find
72．There is/will be no need to
74．Holding the/ his keys in the/ his hand
With the keys held in the / this hand
The keys held in the / his hand
75．I had not / hadn’t drunk
76．What delighted the fans / made the fans delighted
77．to have been destroyed
78．It (suddenly)occurred to him
79．the moment you press
80．Compare these / the two toothbrushes
One Possible Version
Years of school life has taught me a lot of things, of which teamwork is the most important for me.
In fact, I didn’t realize its importance until I was chosen monitor of my class in my senior middle school. At first, I did most of the duties myself while other students cared little about class activities. As a result, I was tired out and depressed. Then I turned to my teacher and he advised me to cooperate with others. Thus I began to recognize the strengths of my classmates and have everyone do their part in class.
It is working in teams instead of on my own that has freed me of trouble and made my work more efficient.