I am a teacher. We are teachers.
但要注意：当表示时间、长度、距离、金钱、度量等词组作主语时，常将其看作是一个整体，谓语动词要用单数形式。例如：Two years is quite a long time. Ten dollars is enough.另外，加减乘除也常当作整体对待，谓语动词也用单数形式。例如：Forty-one plus fifty-nine is one hundred. How much is ninety-nine minus sixty-two?
二、集体名词作主语时，谓语动词的使用
family, class, team等集体名词作主语时，若指一个整体，谓语动词用单数形式；但若指其成员时，谓语动词用复数形式。例如：The family is very big. Their family are watching TV now.
