Every student in our class had an application form in his hand，but no one knew which offic

Every student in our class had an application form in his hand，but no one knew which office .
A. to send it to
B. to send it
C. to be sent to
D. to have it sent

(答案→)A. to send it toB. to send itC. to be sent toD. to have it sent解析：根据句意及句子结构可知，选项部分不定式与疑问词一起作为句子的宾语，在这一结构中，常用不定式的主动结构，可以转换为宾语从句：but no one knew which office he would send it to。注意send sth to sb/sp为固定短语，to为介词，不能省略。

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