资源 标记: Road Building
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1986-01-01 Roads vary from trails to major hard-surface highways. Depending on the local climate and materials available for construction, roads may sometimes be open to traffic for only part of the year. A year-round road is often more expensive to build, and may not always be necessary. As a general rule,...
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1987-01-01 Moving soil for irrigation and road-building is important to good farming. Careful preparation of land for irrigation and good water usage saves water, labor, and soil, and improves crop yields. Improved roads make communication easier between farmers, their suppliers, and their markets. Although...