Be appointed manager 和 be promoted to manager
问题描述：
Be appointed manager 和 be promoted to manager
为什么一个被动有介词一个没有呢
答
Be appointed manager：是任命的经理
be promoted to manager：将会升任为经理（be promoted to —— 被动式动词词组）亲 我问的是 为什么appoint后便不加介词 谢谢因为这里不需要。to appoint 通常接双宾语（所谓直接和间接宾语）：I appointed John the manager of the sales department. 当用被动式表达时，直接宾语做主语，间接宾语留在宾语的位置，无需介词：John was appointed the manager of the sales department. to promote sb to...是动词词组，介词是其中一部分。所以在变成被动式以后，介词 to 必须保留。