able的名词形式是

　　His outstanding ability earned him a place on the team.

　　他非凡的能力为他在队中赢得了一席之地。

　　Both are blessed with an uncommon ability to fix things.

　　俩人都有幸具有不寻常的修理东西的能力。

　　What criteria are used for assessing a student's ability?

　　用什么标准来评定一个学生的能力？