A minor is an alternative field of study that is a complement, or perhaps entirely different from your main field of study.

辅修课是研究领域的一种选择，是一种补充，或许会和你学习的主要领域完全不同。

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Like many of his entrepreneurial brethren in the alternative-energy field, he will be looking for a new business model.

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More importantly, the US market is a shrinking market while the emerging markets provide a green field alternative for fast food and high level growth.

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He has suggested an alternative site in a field further from the main road.

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