Ielts vocabulary Masterclass book + ielts listening & Reading Dictionary: Dominate Proficiency Level Vocabulary for ielts listening, Reading, Writing & Speaking

Pressing = urgent
For example: There is a pressing need for housing in the area.              
Pollutant = a substance that contaminates
For example: The most dangerous gaseous air pollutants released into
the air in urban areas are Sulphur dioxide, nitrogen dioxide, and carbon
monoxide;
Ecosystem = the environment in an area and all the biological life in
it             
For example: Half of these trees could be gone within five years,
threatening jobs and ecosystems.

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Unprecedented = something that has never happened before
For example: Governments were not sure how to deal with the situation
because it was unprecedented in 21st-century life.
Safeguard = protect against something
For example: We must safeguard the environment against the
destruction of habitats and the over-exploitation of natural resources
such as fresh water and fisheries among other issues.

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