2. He was seen to steal your car 

3 . Student is being watched to do the homework by the teacher

4.  you won't be let  do that silly thing again by him

5. the children are made to 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 terrorists

9. Drivers are advised using  an alternative route

10. I am helped to do all these difficult exercises by her  

Giải thích: 

* Let + O + V(bare) ⇒ Sang câu bị động không có từ '' to '' 

* S + see + O + V(ing) ⇒ Sang câu bị động , động từ V-ing vẫn giữ nguyên

* S + advise/ recomend / suggest + doing St 

* Nếu trong câu chủ động mà có các đại từ bất định sau : they , people , everyone , everybody , someone , somebody .... thì sang câu bị động ta không cân dùng by + chúng