单项选择题
A.inform B.informing C.to inform D.will inform
I regret（）the trouble I have caused you.A.toB.atC.forD....
单项选择题I regret（）the trouble I have caused you.
A.to B.at C.for D.on
I must hold（）for any damage which may result from the a...
单项选择题I must hold（）for any damage which may result from the accidents you have caused.
A.your responsible B.you responsible C.you are responsible D.your are responsible
I look forward to（）for this at your earliest convenienc...
单项选择题I look forward to（）for this at your earliest convenience.
A.having your approval B.approved by you C.get your answer D.know your opinion
