average tree

例句：

1. 1. The average temperature in the city is around 20 degrees Celsius.
   这个城市的平均温度大约是20摄氏度。
2. 2.He works hard to achieve an average grade in his exams.
   他努力学习，希望在考试中取得一个平均水平的成绩。
3. 3. The average income of a worker is usually lower than their boss's salary.
   工人的平均收入通常低于他们的老板的薪水。