老师说这个句子中的that为连词 可是and也是连词的啊,这两个连词怎么可能放一起呢?and that different foods provided different amounts of these essentialagents.完整的这段英文是 twentieth century when it was recognized for the first time that food contained constituentsthat were essential for human function and that different foods provided different amounts of these essential agents.

老师说这个句子中的that为连词 可是and也是连词的啊,这两个连词怎么可能放一起呢?
and that different foods provided different amounts of these essential
agents.

完整的这段英文是
twentieth century when it was recognized for the first time that food contained constituents
that were essential for human function and that different foods provided different amounts of these essential agents.