Language is sometimes written as a code so that people can communicate secrets. During     1     Second World War, the German Navy （海军）used a code to send messages. The British broke the code and     2     （learn） about many German plans. The Japanese also used a code to talk to     3     （they） ships at sea. It was called the Purple Code. Although the Americans soon broke this code, the Japanese didn’t know it     4    （break）. In 1942 , the Americans began to use their own code to send     5     （secret）. A few Navajo（纳瓦在人）Indians made this code     6    （base） on their language, which only some American Indians spoke. The code described a few things the American army did. Only they could understand this code, so they went with the army as it fought against the Japanese. These Navajo soldiers promised     7    （keep） this code a secret, even though this could cause their     8    （die）. The Japanese never broke the code because they knew nothing     9     the Navajo language. And the code,     10     connected two languages, helped win the war in the Pacific.

The British have been drinking tea for over 350 years. But in fact, the history of tea goes much     1    (far) back.

The story of tea begins in China. According to the legend, the Chinese emperor Shen Nung was sitting     2    a tree while his servant boiled drinking water, when some leaves from the tree blew into the water. Shen Nung,     3     expert in herbal medicine, decided to try the water his servant created. As a result, it tasted so good that later the drink was     4     we now call tea.

It is     5    (possible) to know whether there is any truth in this story.     6    , tea drinking certainly was established in China many centuries before it had even been heard of in the west. Containers of tea     7    (find) in tombs dating from the Han dynasty (206BC-220AD) before tea was firmly established as the national drink of China in the Tang dynasty (618-906AD). It became     8     a favorite thing that during the late eighth century, a writer     9    (call) Lu Yu wrote the first book entirely about tea, the Ch’a Ching, or Tea Classic. It was shortly after this that tea was first introduced to Japan, by Japanese Buddhist monks who had travelled to China to study before. Tea drinking has become a vital part of Japanese culture,     10    may be rooted in the sprit described in the Ch’a Ching.