Today,I find so many people struggling,often working harder,simply because they are trapped bysimply because they are trapped by old ieads.我不清楚这个句子中 struggling,often working harder,作什么成分,为什么中间不加and.哪位高手帮我分析下句型

Today,I find so many people struggling,often working harder,simply because they are trapped by
simply because they are trapped by old ieads.我不清楚这个句子中 struggling,often working harder,作什么成分,为什么中间不加and.哪位高手帮我分析下句型