Richardwascalledinbythepolicetoanswerquestions

問題詳情：

Richard was called in by the police to answer questions ________ the disappearance of Thomas, whose relatives were so ________ his present situation.

A. concerning; concerning about                   B. concerned; concerning about

C. with regards to; concerned about               D. regarding; concerned about

【回答】

D

知識點：非謂語動詞

題型：選擇題