Combining Sentences through Subordination Definition

Subordination joins clauses that are unequal in importance.

Subordination uses a subordinating conjunction to make one clause dependent on another. The dependent clause is subordinate to the independent clause.

The list of subordinating conjunctions is long, but here are some of the more common ones:

Relationship	Conjunctions	Example
Time	When Whenever After Until Before After	Whenever the afternoon bell rings, a teeming horde of children rush eagerly out of the school building. I never knew what love meant until I met you. My uncle always calls after he watches the news.
Place	Where Wherever	I know a place where blackberries grow wild all along the roadside. Wherever you can find an empty spot, just drop your luggage there.
Cause / Effect	Because Since So that	Since you have to leave early, why don't you arrive a few days earlier too? The cat took off in a panic because the dog started barking and growling.
Condition	If Unless If only	If my ticket doesn't arrive today, I won't be able to fly out tomorrow. He won't listen to you unless you make him turn off the radio and look at you.
Contrast	Although Even though	Although I have called repeatedly, the credit card company has not corrected my account. He still brings her roses even though he knows she is allergic to them.

If you look carefully at the example sentences, you'll notice an important punctuation rule that applies to subordination:
Place a comma after but not before a dependent clause.


Examples:

After the final touchdown, the fans stormed out onto the field.



The fans stormed out onto the field after the final touchdown.

Therefore, whether or not you use a comma depends on the order of clauses in the sentence.