2.
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.
11.
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.
12.
The technology of this straw has developed since the original product was invented years ago. Today, one straw can be used for about 4,000 liters of water. The company that created the straw has also developed many other types of products, and some of them are used when disasters occur. In fact, these products ___________ in several countries, such as Thailand and Ecuador. In the future, these products may allow more people to drink safe, clean water in more areas and on more occasions.