Don't use the bags.The bags are made from plastic (  use Past participle)

The secretary does a lot of work ( đổi thành bị động)

 I am writing a poem ( đổi câu bị động)

a, A poem was  beging wriiten

b. A poem is beging writing 

c. A poem are being written

d. A poem is beging written

My elder brother will win the race ( đổi câu bị động)

a. the race will be won by my elder brother 

b.The race will been won by my elder brother 

c.the race will be win by my elder brother 

d.The race is won by my elder brother 

Nam's father has just bought another villa ( đổi câu bị động)

a.Another villa will just be bought by Nam's father

b.Another villa has just been buyed by Nam's father

c.Another villa has just been bought by Nam's father

d.Another villa has just been bought by Nam's father