A) She connected the home work last week.
Passive voice: The home work was connected last week (by her).
B) We bought a dog yesterday.
Passive voice: A dog was bought yesterday (by us).
C) The girl will write a composition about the enviroment.
Passive voice: A composition about the environment will be written (by the girl).
D) They are going to teach math classes next week.
Passive voice: They are going to be taught math classes next week.
E) They are painting their house next week.
Passive voice: Their house is being painted next week (by themselves).