Milk was one of the main human foods long 25________ history was written. It will probably remain one 26________ ________ ________ there are animals that give milk. The old word “milk” came from Sanskrit (梵文), one of the oldest languages 27________ (know) to man. A very old picture of milking animals, drawn five thousand years ago, has been found. People got their milk from their own animals. But in modem times new inventions made the milk industry 28________ big business. In 1851 Gall Borden found a way to take some of the water from milk. This made 29________ keep longer. Four years later, Louis Pasteur introduced a way 30________ (kill) the bacteria in milk. So in the same year a special milk bottle was made. This was followed by the invention of machines that 31________ fill bottles with milk. These discoveries meant that milk could be stored longer. Some people believe that milk drinking will become less popular than it has been. But remember how long milk has been an important food and think of the many ways in which it is useful. It seems safe to say 32________ milk industry will always be important.
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