`1` The letters are typed in the office by Mary

`-` cấu trúc bị động thì HTĐ: S+is/am/are+(not)+V3/ed + (by+O).........

`-` vì letters đã xác định nên thêm the

`-` letters số nhiều nên dùng are

`2` You will be helped by his father tomorrow.

`-` cấu trúc bị động với be : S+will+(not) +be+V3/ed+(by+O)....

`-` theo nguyên tắc : chốn-by-gian thì by his father đứng trước tomorrow

`3` Human life has been completely changed by science and technology.

`-` cấu trúc bị động thì HTHT : S+have/has+(not)+been+V3/ed+(by+O).....

`-` human life là số ít nên dùng has

`4` This bottle was broken by Peter.

`-` cấu trúc bị động thì QKĐ : S+was/were +(not ) +V3/ed+(by+O)....

`-` this bottle là số ít nên dùng was

`5` English is being learnt in the room

`-` cấu trúc bị động thì HTTD : S+is/am/are+being+V3/ed+(by+O).....

`-` engish là số ít nên dùng is

$@Mayumi Dojima$

`1.` Letters are typed in the office by Mary.

`2.` You will be helped by his father tomorrow.

`3.` Human life has completely been changed by science and technology.

`4.` This bottle was broken by Peter.

`5.` English is being learnt in the room. 

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`+` Cấu trúc câu bị động:
`-` Thì TLĐ: S + will + be + Ved/V3 + (BY  O)
`-` Thì HTĐ: S + am/is/are + Ved/V3 + (BY  O)

`-` Thì QKĐ: S + was/were + Ved/V3 + (BY  O)
`-` Thì HTHT: S + have/has + been + Ved/V3 + (BY  O)
`-` Thì HTTD: S + am/is/are + being + Ved/V3 + (BY  O)