important theories的用法和样例：
例句
- Special relativity and quantum mechanics were two major theories that appeared subsequently.
狭义相对论和量子力学是相继出现的两个主要理论。 - The two major theories on the origin of cancer both implicate GSH as a putative protective factor owing to its dual function as antioxidant and detoxifying agent.
有关癌症发生原因的两个主要理论都因谷胱甘肽所具抗氧化剂与解毒剂双重机能，而推定谷胱甘肽应有保护预防的功能。
