▲to a man 是习语，意思是 without exception（无一例外），主要用于书面语，表示强调，英语词典更详细的解释是 used to emphasize that sth is true of all the people being described。如：

To a man, they all agreed. 他们全都赞成此事。 

Economists, almost to a man, were sceptical. 经济学家几乎无一例外地持怀疑态度。

To a man, we have all taken a keen interest in the business. 我们无一例外都对此事有很大的兴趣。 

They died, to a man, when they tried to break out. 他们企图逃走的时候全都丢掉了性命。

▲We were for the change 的意思是“我们都支持要作出改变”，句中的 for 表示“支持”。又如：

Are you for or against the plan？你是支持还是反对这个计划？

Some people were for the strike and others were against it. 有些人赞成罢工，另一些人反对。

▲句意思是：我们所有人都支持作出改变。