第四句型：主语 + 及物动词 + 双宾语
有些动词后面需要或可以接双宾语结构，如：give, write, buy, send, make等
You may send him an E-mail or write him a letter.
这个句子也可使用以下结构：
You may send an E-mail or write a letter to him. 所以 to 和 for 是连接双宾语结构的重要介词。
该句型的重点是要记住以下短语，特别是所用的介词：
to cure of
to accuse of
to convince of
to inform of
to notify of
to clean of
to warn of / against
to cheat of
to rob of
例如：
We have to inform the family of the patients condition as soon as possible. / Have the family been informed of the patients condition?
注意下面句子的结构变化：
May I ask you a question? May I ask a question of you?
直接和间接宾语的位置与上面短语有何不同?