One benefit the author mentions is that the system______.
A: uses no electricity
B: has a fire-safety shutoff
C: does not pollute the air in the house
D: pollute the air in house
A: uses no electricity
B: has a fire-safety shutoff
C: does not pollute the air in the house
D: pollute the air in house
举一反三
- One benefit the author mentions is that the system ______ A: uses no electricity B: has a fire-safety shutoff C: docs not pollute the air in the house D: requires less insulation in house walls
- The air in this area got A: to pollute B: pollute C: polluting D: polluted
- What gas does not pollute the air A: Oxygen. B: Hydrocarbons. C: Carbon monoxide. D: Nitrogen oxides.
- Cars are currently the major source of air (__)(pollute).
- The air inside .a house on office building often has more contaminants（）the heavily polluted air outside. A: than does B: as C: as some that are D: than that of