下列情况中，质量会发生改变的是（     ）

C

    There is a big demand (需求) for English teachers in China. The country develops at a high speed, so it needs lots of volunteers who can teach primary school students conversational (对话的) English skills in China. Global Crossroad is mainly connected with several Chinese public schools. And most of them are in the countryside. Non-native English speakers are also invited to join this project.

    With the growth of the country's economy, the demand for English education in China is growing. As China continues to be a global business country, the importance of English education is increasing as well. Many public schools in China have an "English Comer", which is a place of the classroom designed (设计) and set aside for teaching and learning English. These schools are in need of international teachers to teach English.

    Most schools in the countryside in China are searching for good English teachers. Your time and efforts are so important in improving these students' English skills and helping them get more equal (平等的) chances to work in the future.

1787年，美利坚合众国宪法对独立后的美国意义重大，其重要作用是
①结束了松散状态，维护了国家统一　②满足了人民群众对权益的要求　③确立了美国的责任内阁制　④促进了美国资本主义的发展

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