a- A new road is being build.
b-All the postcards have been bought. (ce n'est pas necessaire de mettre "by someone")
c-During the interseason, the shop will close. (je crois)
d-The reservation is visited by a lot of tourists. (ou by lots of tourists c'est pareil)
e- During the renovation, the museum is closed.
Voila j'espere t'avoir aider :)