A 、be sent B 、must be sent C 、be must sent D 、must send

A 、Do; planted B 、have; been planted 　 C 、Are; planted　　 D 、Have; planted

A 、was; building B 、is; built C 、was; built　　 D 、did; built 　　

A 、is cleaning B 、will be cleaned　　 C 、be cleaned 　　 D 、is cleaned

A 、are bought B 、will be bought C 、have been bought D 、were bought

A 、was heard to sing B 、heard to sing 　 C 、was heard sing D 、heard sing

A 、putted B 、be putted 　　　 C 、is put 　　　 D 、be put

A 、be paid more attention to B 、be paid more attention C 、pay more attention to D 、pay more attention

A 、are cleaning B 、are cleaned 　　　 C 、is cleaned D 、have been cleaned

A 、is building B 、has been built　 C 、is being built　 D 、is built