■平均每天有10个学生缺席。

误：An average of 10 students was absent each day.

正：An average of 10 students were absent each day.

析：“an average of＋复数名词”作主语，谓语用复数，而“the average of＋复数名词”作主语，谓语通常用单数。如：The average of these numbers is 50.(这些数的平均数是50)。

■我们平均每天收到10封信。

误：In (the) average we receive ten letters each day.

正：On (the) average we receive ten letters each day.

析：on (the) average(平均)是固定短语，不用介词 in。

■昨天的平均气温是多少?

误：What was the temperature of average yesterday?

正：What was the average temperature yesterday?

析：average 可用作形容词(意为“平均的”)直接放在名词前作定语。又如：The average age of the boys in this class is fifteen. (这个班男生的平均年龄为15岁)。