a. This question has been answered by nobody.
b. He should be informed immediately by you.
c. The pyramids were built by the ancient Egyptians.
d. Ann has to be invited by us.
e. It mustn't be left outside the fridge.
f. Was a new car bought by you?
g. The invitations have already been sent by him.
h. Some sandwiches were given us by Peter.
i. My old clothes were thrown away by my mum.
j. He is going to be paid tomorrow by us.