Tim and Alan worked together for their school's science club. They wanted to do something to help1people. They were inspired(启发) to make the backpack after2uncle died on the street. Because of mental(精神的) illness, Tim's uncle3homeless and started living on the street. He missed his uncle and wanted to create a 4place for homeless people.
So they got the idea of building a home5the homeless. Their amazing work is a big back pack. It weights two6. When it is folded(折叠) , it can be carried on the shoulder as a backpack. And when it spreads 7, the backpack will become a "house". The solace blanket(毛毯) in it keeps people .8 during the cold winters. It's 6℃ to 7C warmer inside than outside. During the hot summer months, the backpack can be turned over 9the space blanket is on its top. It will be10cooler inside. The boy hope that one day they will see homeless people using their invention on the street. What a wonderful thing the boys have done!