来自刘中华的问题
【About10milliondolphinsaresaid________inthepast15years．（）A.tohavekilledB.tokillC.tohavebeenkilledD.tobekilled】
About 10million dolphins are said ________ in the past 15years．（）
A.to have killed
B.to kill
C.to have been killed
D.to be killed
