as seen in its stable economic growth = as is seen in its stable economic growth。这是as引导的比较分句,作rapid development的后置修饰语。 as后省略了is。
Thanks to the strategy of developing China's western region, Tianzhu has witnessed rapid development, as seen in its stable economic growth, increased competitiveness and living standards, optimized industrial structures, and strengthened infrastructure development.The county changes with each passing day. Today, it has taken on a new look, featuring a nice environment, outstanding culture and education, better comprehensive services and living conditions, and a vibrant economy.