阅读下面短文，在空白处填入一个适当的词，或填入括号中所给单词的正确形式。

    In much of Asia, especially the so-called “rice bowl” cultures of China, Japan, Korea, ____Vietnam, food is usually eaten with chopsticks.

    Chopsticks are usually two long, thin pieces of wood or bamboo. They can also be made of plastic, animal bone or metal. Sometimes chopsticks are quite artistic. Truly elegant chopsticks might ____ (make) of gold and silver with Chinese characters. Skilled workers also combine various hardwoods and metal ____ (create) special designs.

    The Chinese have used chopsticks for five thousand years. People probably cooked their food in large pots, ____ (use) twigs（树枝）to remove it. Over time, ____ the population grew, people began cutting food into small pieces so it would cook more quickly. Food in small pieces could be eaten easily with twigs which ____(gradual) turned into chopsticks.

    Some people think that the great Chinese scholar Confucius, ____ lived from roughly 551 to 479 B.C., influenced the ____ (develop) of chopsticks. Confucius believed knives would remind people of killings and ____ (be) too violent for use at the table.

    Chopsticks are not used everywhere in Asia. In India, for example, most people traditionally eat ____ their hands.

2011年9月4日，中国企业500强在四川成都发布，中国石油集团公司、中国石油天然气集团公司和国家电网公司排名前三。名列前茅的还包括中国移动、中国铁建、中国中铁、农业银行，这些企业无不是国字号企业。这告诉我们国有经济（    ）