Just as ……，so，是从属连词，其中just,有时可以省略。As引导的是方式状语从句（常常放句首）；so引导的是主句。表示：正如……一样，……
请看经典例句：
Just as societies were facing their histories, so, too, were countless individuals.（希拉里，《亲历历史》P313.）
正像社会面临历史问题一样，无数的个人也面临着历史带来的问题。
注意，这个主句采用了倒装结构。且采用省略句形式。
Just as John has changed, so has his wife
约翰变了，他的妻子也变了。
《柯林斯高阶英汉双解学习词典》
注意，这个主句采用了倒装结构。且采用省略句形式。
Just as large companies are having to cut back, so small businesses are being forced to close.
大公司不得不紧缩，小企业则被迫关闭。
《牛津高阶英汉双解词典》
Just as sound travels through the air in waves, so electricity travel through the air in what we call radio waves.
正像声音以波的方式在空气中传播一样，电以我们称之为无线电波的方式在空气中传播的。
Just as French people enjoy their wine, so the British enjoy their beer.
正如法国人喜欢喝白酒一样，英国人喜欢喝啤酒。
As the cost of keeping money in the bank increases, so it’s spent faster. 随着在银行存钱的费用增加，人们的钱花得也更快了。
Just as they must put aside their prejudices ,so we must be prepared to accept their good faith.
正如他们必须抛掉偏见一样，我们必须准备好接受他们的诚意。
Just as too much harmony is tiresome in music ,so,in life ,too many benefit annoys us.
正如音乐中太多的和声令人厌烦一样，生活中太多的福利也让我们烦恼。（托福考题）
Just as radio and TV have changed many aspects of our lives ,so laser will bring about great changes in science and technology.
正如广播和电视改变了我们生活的许多方面一样，激光也将给科学技术带来巨大的变化。
Just as the soil is a part of the earth, so is the atmosphere.
正如土壤是地球的一部分一样，大气也是。
注意，这个主句采用了倒装结构。且采用省略句形式。
Just as a book is often judged outwardly by the quality and appearance of its cover,so a person is judged immediately by his appearance.
正如一本书往往以封面的质量和外观来评判一样，一个人也会通过外观立即被评判。
Just as the value of a telephone network increases with each new phone added to the system ,so does the value of a computer system increase with each program that turns out.
正如电话网络的价值随着系统中每一部新电话的增加而增加一样，计算机系统的价值也随着每一个程序的产生而增加。(考研真题)
注意，这个主句采用了倒装结构。且采用省略句形式。
Just as the builder is skilled in the handling of his bricks, so the experienced writer is skilled in the handling of his words.
正如建设者善于处理砖块一样，有经验的作家也善于处理自己的文字。
通过以上经典例句的分析，可以说，这个句型的主句倒装与否，是选择性的。