英语中主句和从句的结构要一样么?

题目

英语中主句和从句的结构要一样么?
比如 Although early soap operas were first aired on evening radio in the 1920s,they were moved to the daytime hours in the 1930s.

答案

其实你可以从阅读中自己寻找答案.
主从句结构无需一样.
比如：If the weather is fine,we will go outing.
When I was a boy ,my mother would always take me out.