A.They are built to produce more fruits and wheat.B.They are naturally air-conditioning and water-saving houses.C.Most of green houses are used only in winter for heating.D.People try to save energy as much as possible.
A.They are built to produce more fruits and wheat.
B.They are naturally air-conditioning and water-saving houses.
C.Most of green houses are used only in winter for heating.
D.People try to save energy as much as possible.