Change the following sentences into active or passive form. 
 (a) They pleased us all. 
(b) Who has broken the plate? 
(c) I am going to open a bank account. 
(d) Let him sing a folk song. 
(e) My pen has been lost. 
Change the following sentences into active or passive form. 
(a) Rome was not built in a day. 
(b) Write a letter to your friend. 
(c) When will you return my book? 
(d) He is going to do marketing. 
(e) I have to do the work.