The most harmful contaminant in the atmosphere is sulphur dioxide, a gas produced by combustion of fossil fuels like coal and oil;
(The most harmful contaminant in the atmosphere; is; sulphur dioxide) (a gas; produced; by combustion of fossil fuels like coal and oil)
The most harmful contaminant in the atmosphere a gas
is produced
sulphur dioxide
by combustion of fossil fuels like coal and oil