雅思作文中一句话帮我分析其语法结构这是图表题,作者写到：The amount of goods transported by wa_其他解答

雅思作文中一句话帮我分析其语法结构
这是图表题,作者写到：
The amount of goods transported by water was constant from 1974 to 1978,where it showed an exponential growth,rising to almost 60 million tonnes after which is plateaued for about 20 years before starting to rise gradually again.
1.1978 后的 where it showed ,是什么从句?
2.60 million tonnes after which,这里的 after,是跟 60 million tonnes after,还是应该 after which 一块的呢?我认为是 60 million tonnes after ,但which后是什么从句呢?
3.老师说过 before,代表意思是 “才”,后面算什么,现在分词作状语吗?

人气：411 ℃　时间：2020-05-20 15:14:33

解答

where it showed 是1978年的定语从句,是把1978当做一个时间点来说,从1978年开始增长的.

which引导的是定语从句,先行词是 60 million tonnes 这一数量.after which是一起的,也就是after引起一个时间状语从句.只不过这个时状从同时又是与前一句紧密相连的定语从句罢了.即在60 million tonnes 这一数量稳定了将近20年之后,又开始了逐渐地增长.

before这里是介词,+Ving 做时间状语.和可以before +时间状语从句转换.before it started to rise gradually agian.