Task 4 :
`1.` Nina has bought this car.
`2.` The police has found the thief.
`3.` Someone has found her pen.
`4.` I have finished the reports.
`5.` Nina has bought these pencil cases.
* Giải thích cách làm :
Câu bị động : S + have/has been + VPII + (by O)
`⇒` Câu chủ động : S + have/has + VPII + O