Tom thought it was an honor to speak in the ceremony.A. to inviteB. to be invitedC. invit

问题补充：

Tom thought it was an honor to speak in the ceremony.

A. to invite

B. to be invited

C. inviting

D. having invited

答案：

A. to invite

(答案→)B. to be invited

C. inviting

D. having invited

解析：考查it充当形式主语。It是形式主语，Tom和invite构成被动的关系。to be invited to speak in the ceremony是真正的主语。句意：Tom认为被邀请在庆典上发言是一件光荣的事情。