Have you ever thought about how astronauts wash their clothes without gravity ( 重力 )? It’s not easy. There’s no washing machine on the International Space Station (ISS). Luckily, this may not be a problem in the future. Russian scientists are making a 50______ washing machine for astronauts to use in space. The washing machine is different from the ones we use. It doesn’t need water. It 51______ carbon dioxide from the air that the astronauts breathe out. Then, it uses high pressure to turn that carbon dioxide into a 52______ that can help clean clothes. This could make astronauts’ lives much 53______. Because normal washing machines can’t work in space, astronauts living aboard the ISS need to bring as many clothes as possible. Sometimes they even ask other spacecrafts to bring clean clothes from Earth.