Question: I once asked a question if the sentence 

> 
> jeder muss dafür verantwortlich sein, was er gesagt hat
> 
> 
> 

is correct and was told that it is acceptable and that the verb must go at the end of its own clause before any subordinate clause. 

However, I was also told by a native speaker that this sentence could also be enclosed by one, like

> 
> Jeder muss für das, was er gesagt hat, verantwortlich sein.
> 
> 
> 

or

> 
> Jeder ist für das, was er gesagt hat, verantwortlich.
> 
> 
> 

I just wonder that in the first sentence above the verb 'sein' goes to the end of the entire sentence after the subordinate clause. It really annoys me how should I correctly build the German main clause and subordinate clause and is there a rule I can follow? And 

Take the following sentences. 

> 
> 1. Sobald ich Zeit habe, werde ich dir helfen.
> 2. Ich werde dir helfen, sobald ich Zeit habe.
> 3. Ich werde dir, sobald ich Zeit habe, helfen.
> 
> 
> 

I can understand the first two sentences well but I still get confused by the third one.

Answer: 
Don't let the third sentence type confuse you. The subordinate clause is an insertion and the outer sentence structure is not changed by it. The normal sentences would be

> 
> Jeder ist für das verantwortlich.
> 
> 
> Ich werde dir helfen.
> 
> 
> 

The conjugated verb is at the second position as usual. The tricky part is were to insert the subordinate clauses. In the first example right after the part that is restricted by it. In the second example I would assume it is inserted behind the object.

However, there are [dependent subordinate clauses](http://canoonet.eu/services/OnlineGrammar/Satz/Komplex/Ordnung/Subordination.html) which work differently.
Actually, all of the above are correct. Especially the last three examples are all correct. You are safe using your first example - the one you came up with yourself.

If you want to read about subordinate clauses in German, go to the following page: <http://www.mein-deutschbuch.de/lernen.php?menu_id=123>