celebrate reached buildings turned house gathered Thousands of people (1) ___________ at the August Revolution Square in front of the Hanoi Opera House from 8:30 p.m to 9:30 p.m on March 29 to join the 2014 Earth Hour Campaign. The lights and unnecessary electrical appliances of the (2) ___________, shops and local families around the Hoan Kiem Lake and the Hanoi Opera House were (3) ___________ off during one hour of the campaign. A wide variety of unique arts performances were held at the Square to (4) ____________ this year’s Earth Hour. This is the sixth time Vietnam responds to the Earth Hour campaign launched by the World Wild Fund for Nature (WWF). ‘Let’s unite to save the Earth’ is the message that this year campaign conveys to people around the world.