teacher's pay remained the biggest cost,reaching 50%of total spending in 1991 and ending at 45% in

问题描述:

teacher's pay remained the biggest cost,reaching 50%of total spending in 1991 and ending at 45% in
2001.
其中的reaching和ending 用的是什么语法啊,为什么加动词的ing形式,谁能仔细讲解一下啊?

用的语法是伴随状语,动词+ing以动名词的形式作伴随状语修饰主语,在这句话中reaching 50% of total spending的意思teacher‘s pay达到了50% of total spending,ending at 45%的意思是teacher's pay 终止在了45%.其实...