average flow

例句：

1. 1.The average temperature in winter is below freezing point.
   冬天的平均温度低于冰点。
2. 2. The average salary for a software engineer is $70,000 per year.
   软件工程师的平均年收入为7万美元。
3. 3. The average life expectancy of people born in the 1960s is 78 years old.
   1960年代出生的人的平均预期寿命为78岁。