I.

1. she has been heard to sing this song many times.

2. he was seen to steal your car.

3.  our work is being watched by the teacher.

4. You will not be let to do that silly thing again.

5. the children do not be made work hard.

6. he was made to work all day

7. the woman was seen putting the jewelry in her bag by the detective

8.  the hostages were made to lie down by the terroists

9. drives are advised to use an alternative route by the police.

10. i am helped to do all these difficult exercises

II.

1. your book must be opened

2. your hat must be taken off

3. that silly thing musn't be done again

4. let's them be told about you

5. don't let you be seen

III.

1.

i was advised to sell that house

2. we were begged to help him

3. it is ordered that the floor be cleaned.

4. it is recommended that the job be done

5. he was urged to visit her parents as soon as possible

 IV.

1 It is dangerous for us to take the short cut.
=>> It is dangerous for the short cut to be taken
2 you need to have your hair cut
=>> Your hair needs cutting
=>> Your hair needs to be cut
3 You must see it to believe it
=>> It must be seen to be believed (bừa =)))
4 He wants someone to take some photographs
=>> He wants to have some photographs taken
5 We enjoy writing letters
=>> We enjoy letters being written.