What does '60+' mean? The logo of Earth Hour is '60+. The number 60 is for the 60 minutes of Earth Hour, and the plus invites people to keep on taking action even after Earth Hour is finished. In fact, people who join Earth Hour say that taking part makes them want to do more for the environment. The climate activist Greta Thunberg says that 'Earth Hour is every hour of every day." 1. When is Earth Hour? A. annual event C. in 2007 2. What do people do for Earth Hour? A. Switch off non-essential lights. B. at the end of March every year D. 60 minutes B. Watch TV to participate in the campaign. C. Raise awareness of environmental issues D. Switch on the lights at famous buildings. 3. What does the word "go dark" mean? A. walking in the dark C. switch off lights B. living in the dark D. turn on lights 4. According to the passage, which of these have gone dark for Earth Hour EXCEPT ? A. The Petronas Towers B. The Eiffel Tower C. The World Wide Fund for Nature (WWF) D. The Sydney Opera House