A.the building are too high |
B.the flow of air indoor is limited |
C.the building materials are harmful |
D.people don't want to waste energy |
A.all kinds of offices | B.all kinds of houses |
C.every modern house | D.every old house |
A.take in | B.bring up | C.give out | D.turn into |
A.change oxygen into pollutants |
B.absorb all the pollutants |
C.make your houses more prettier |
D.absorb pollutions and let out oxygen |
A.plant all kinds of plant |
B.plant more trees. |
C.have the same kind of plant |
D.have different kinds of plants |