核心问题
（a）We agreed that his criticism was to the point.
(b) We were agreed that his criticism was to the point.
我们认为他的批评很中肯。
上句中的动词的主动形式(agreed)与被动形式(were agreed)为什么具有相同的意义？
词典解答
英语里有许多形容词与过去分词(被动分词)具有完全相同的形式。骤然看来，它们是过去分词，但实际上却是形容词，例如：agreed, astonished, bored, broken, convinced, devoted, delighted, disappointed, interested, relieved, satisfied, tired, worried 等等。这样的形容词有很多是用来描述人的精神状态或态度(a state or attitude of mind)的。上句中的 were agreed 并不是被动结构，而是系表结构。类例：