Subordinating conjunctions connect parts that aren’t equal. In fact, you can tell by their name that they make a phrase subordinate to the main phrase or clause.
Common subordinating conjunctions are after, although, because, before, even though, since, though, and when.
Key to using subordinating conjunctions correctly is to remember that a subordinating conjunction sets off a phrase, so there should always be words with it.
When a subordinating conjunction appears at the beginning of a sentence, the subordinating phrase is always set off with a comma. When a subordinating conjunction appears at the end of a sentence, the subordinating phrase is not usually set off with commas.
The exceptions (and there are always exceptions, right?) are when you use words like although or even though at the end of a sentence. Because these set-off phrases show contrast, they still get a comma, even when they are used at the end of the sentence.
Although I tried, I could not outrun the werewolf.
I could not outrun the werewolf, although I tried.
Because my alarm clock did not go off, I missed the full moon and will now have to wait until next month to go out and play.
I missed the full moon and will now have to wait until next month to go out and play because my alarm clock did not go off.
You will notice the comma with the although phrase, no matter where it appears in the sentence, but the because phrase follows the standard “rule.”
It’s also important to note that although cannot stand alone like a conjunctive adverb, which will be discussed on the next page.
The above example is a common, incorrect usage of although and actually makes a sentence fragment, which is a serious grammatical error.