3. To drink clean water, one side of the straw is put into the water, and people simply drink the water from the other side. The water goes through a special fiber in a plastic tube. The fiber blocks even very small materials to prevent them from entering the mouth. In this way, the water that comes out is ___________. The materials contain several kinds of bacteria, and the straw can remove nearly 100 percent of them.
7. Today, many efforts are being made to provide people around the world with safe drinking water. One example is a company that developed a straw to produce clean water. This special straw is used the same way people use a simple regular straw. When it was invented, a terrible disease was causing problems for the people living in Africa. ___________, the original purpose of developing the straw was to improve people’s lives by taking the disease out of their lives.
