1, Letters are typed by Mary in the office

2, You will be helped by his father tomorrow 

3, Human life has been changed by Science and technolgy

4, This bottle was broken by Peter yesterday

5, Tea can't be made with cold water

6, A cake is being cut with a sharp knife by Mary 

7, English is spoken in almost every corner of the world

8, This mmachine musn't be used after 5:30 p.m

9, After class, the chalk board is erased by the students

10, The flowers are being watered 

1. Letters are typed in the office.

2. You will be help by his father tomorrow.

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

4. This bottle was broken by Peter yesterday.

5. Tea can't be made with cold water.

6. A cake is being cut with a sharp knife by Mary.

7. English is spoken in almost every corner of the world.

8. This machine mustn't be used after 5:30 p.m.

9. After class, the chalkboard is always erased by the students.

10. The flowers are being watered.

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