When did they invent the personal computer.用被动语态改写

When did they invent the personal computer.用被动语态改写 When did they invent the plane?改为被动语态. when did they invent the personal comp When did he invent the telephone?变被动语态 把下列主动语态改为被动语态：when did they build the house?hav 转为过去式的被动语态 The old woman took care of the cats.When did they When did they make these cars?的被动语态及The policeman saw a thie They must repair the computer now(改为被动语态) When did he clean the window?怎样改为被动语态 what did they invient the machine 的被动语态 How often did they watch the football 改为被动语态 when did play 为什么是被动语态