${1.}$ Letters are typed in the office by Mary .
→ bị động HTĐ: S + is/am/are (not) + V3/ed + (by+O) + time
${2.}$ Human life has been completely changed by science and technology.
→ bị động HTHT: S + have/has (not) + been + V3/ed + (by+O) + time
${3.}$ This bottle was broken by Peter.
→ bị động QKĐ: S + was/were (not) + V3/ed + (by+O) + time
${4.}$ English is being learnt in the room by them.
→ bị động HTTD: S + is/am/are (not) + being + V3/ed + (by+O) + time
${5.}$ Her telephone number isn't known by me.
→ bị động HTĐ
${6.}$ I was sent a present last week.
→ bị động QKĐ
${7.}$ We were given more information by her.
→ bị động QKĐ
${8.}$ Some of my books have been taken away.
→ bị động HTHT
${9.}$ Why wasn’t he helped ?
→ bị động QKĐ
${10.}$ How many games have been played by the team ?
→ bị động HTHT
