Listen and read.     Mr Quang: Good morning, class. Today’s lesson will start with Mai and Nam’s talk about some of the causes and consequences of global warming. Would you like to go first, Mai? Mai: Yes, thank you. First, let me remind you what global warming refers to - it’s the increase in the earth's temperature because of certain gases in the atmosphere. Nam: Exactly. These gases are mainly produced through human activities. For example, burnt for energy, fossil fuels release large amounts of carbon dioxide into the atmosphere. Mr Quang: But how do these gases make the earth warmer? Mai: Well, they act like the glass in a greenhouse. Trapping too much of the sun’s heat, they stop it from escaping back into space. This makes the planet hotter and hotter. Nam: That's right. That’s why these heat-trapping pollutants are known as greenhouse gases, and their impact is called the greenhouse effect. Mai: Global warming is also linked to rising sea levels. As temperatures rise, polar ice caps melt faster, adding more water to oceans. Higher sea levels can also lead to floods. Nam: Each year, the consequences of global warming become more serious, and its negative impact on the environment and people gets stronger. Mr Quang: Good job! Thank you for sharing the information.