The gases in the atmosphere are essential for life on Earth.

The gases expand when heated.

The noble gases are a group of chemical elements with similar properties.

The inert gases are found in the last group of the periodic table.

The police tear-gases the protesters to disperse the crowd.

The protesters were affected by tear gases during the demonstration.

The police tear gases the protesters to disperse the crowd.

Nerve gases are highly toxic chemical compounds.

The off-gases from the factory are harmful to the environment.

The soldiers were exposed to mustard gases during the war.