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。
2
Minor works within the existing house, including the reinstatement of a roof top 'widow's walk' platform, complement the rear extension, which protrudes from under the existing roof.