As an important component of the double-tier operation system, the collective operation in China' s rural areas is based on the collective ownership of rural land.

农村集体统一经营以农村土地集体所有为基础，是双层经营制度的重要组成部分。

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Universal coverage is never as universal as its proponents want it to be, and it usually results in a double- or triple-tier system as the upper-middle classes flee.

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This last tier will either be a single or double based on if the market was able to bounce to 1090-1100.

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The personable Mr. Young foresees a continued double-digit growth in years to come as marketers start pushing into second and third tier cities.

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