谓语动词由none but后面的名词面的名字来确定单复数。

none but 只有

None but the well bred man knows how to confess a fault.

None but the aged stay at home.

None but he is often late for school.

None but fools haveever believed it.

Nothing but, 泛指but后事物以外的任何事物。

There is a variety of fruits, but he chose nothing but an apple.