选择1.－I wonder why he left without a word.－He（ ）some trouble

选择1.－I wonder why he left without a word.－He（ ）some trouble for he looked dull.A.could have had B.should have had C.can have had D.must have had2.The manager discussed the plan that they would like to see( )the next year.A.carry out B.carrying out C.carried out D.to carry out3.It's necessary to be prepared for a job interview.( )the answers ready will be of great help.A.To have had B.Having had C.Have D.Having改错1.Add three to four makes seven.2.He gets lost.I can say that he can be a stranger to this city.是单句改错