温明娜：state

　　n. (名词)

　　她身体状况很糟糕。

　　误 She is at a poor state of health.

　　正 She is in a poor state of health.

　　析 state作“状态”“状况”解时,常用于be in a state of sth 的结构,表示“处于某种状况〔情况〕”,这里介词用in,不用at。

　　国家元首在政治中起关键作用。

　　误 The head of the state played a key role in politics.

　　正 The head of state played a key role in politics.

　　析 用head of state表示“国家元首”时, state前不加冠词。

　　美利坚合众国位于北美洲。

　　误 The United States are located in North America.

　　正 The United States is located in North America.

　　析 以s结尾的表示国家、机构等的专有名词一般视作单数。