there was a increase in this rate,followed by a steady fall in the next five years.逗号加上followed by那半句是什么语法?

问题描述:

there was a increase in this rate,followed by a steady fall in the next five years.
逗号加上followed by那半句是什么语法?

there was 【an】increase in this rate,followed by a steady fall in the next five years【an】
followed by a steady fall.是非谓语动词做状语,伴随状语.