What is the actual meaning of so that was a lie?
So that was a lie is used when something said in the past proves to be wrong.
The meaning of “so that was a lie” can be different according to the context. It probably means to say that a statement made earlier was a lie.
How to use “So that was a lie” in a sentence. Here is one example:
Trump said that he would build a wall across the Mexican border. There is no any chance that the wall will be built. So that was a lie.
I hope that you are clear with the meaning of “so that was a lie”.