$\text{1.}$ Letters are typed in the office by Mary.

$\text{→}$ Thì HTD: S + are/ is/ am + Ved/ P2 + by

$\text{2.}$ You will be helped by his father tomorrow.

$\text{→}$ Thì TLD: S + will be + Ved/ P2 + by

$\text{3.}$ Human life has been completely changed by science and technology.

$\text{→}$ Thì HTHT: S + have/ has + been + Ved/ P2 + by

$\text{4.}$ This bottle was broken by Peter.

$\text{→}$ Thì QKD: S + was/ were + Ved/ P2 + by

$\text{5.}$ English is being learnt in the room.

$\text{→}$ Thì HTTD: S + is/ are/am + being + Ved/ P2 + by.

$\text{6.}$ My mind can't be changed.

$\text{→}$ Modal V: S + modal V + be + Ved/ P2 + by

$\text{→}$ nobody mang nghĩa phủ định

$\text{7.}$ I hadn't been told about it.

$\text{→}$ Thì QKHT: S + had been + Ved/ P2 + by

$\text{8.}$ Her telephone number isn't known by me.

$\text{→}$ Thì HTD

$\text{9.}$ The children will be brought home by my students.

$\text{→}$ Thì TLD

$\text{10.}$ I was sent a present last week.

$\text{→}$ Thì QKD