Extreme heat is becoming increasingly common across the globe. It is an     1     (extreme)dangerous weather condition where the temperatures are much hotter than average. It’s clear that how hot future summers will get depends on     2     humans do to stop climate change.Governments appeal to people to reduce greenhouse     3     (gas)—like methane (甲烷) and carbon dioxide (CO₂) -in the atmosphere. Also, they will set up public cooling stations     4    (protect) people at risk.