A. What are Subordinating Conjunctions?
A subordinating conjunction is a word or phrase that links a dependent clause to an independent clause.
- Independent Clause: A complete sentence that can stand on its own.
> We cancelled the picnic. - Dependent Clause: An incomplete sentence that cannot stand on its own.
> because it was raining
The subordinating conjunction (because) joins these two, showing the relationship between them and creating a single, complex sentence:
We cancelled the picnic because it was raining.
These conjunctions are essential for creating complex sentences and showing sophisticated relationships between ideas, such as time, cause, condition, and contrast.
B. Categories of Subordinating Conjunctions
Here are the most common subordinating conjunctions, grouped by their function:
| Function | Conjunctions | Example |
|---|---|---|
| Time | when, while, since, as soon as, before, after, until | After the movie finished, we went for a coffee. |
| Cause/Reason | because, since, as | I'm late because my car broke down. |
| Condition | if, unless, provided that, in case, assuming that | You won't pass the exam unless you study. |
| Contrast/Concession | although, even though, whereas, while, though | Although he is rich, he is not happy. |
| Purpose | so that, in order that | She is studying hard so that she can get into a good university. |
| Place | where, wherever | I will follow you wherever you go. |
C. The Golden Rule of Punctuation
The punctuation for subordinating conjunctions is simple and absolute. It depends on the order of the clauses.
Rule 1: Dependent Clause First = Comma
If the sentence begins with the dependent clause (and its subordinating conjunction), you must use a comma to separate it from the main clause.
Because it was raining, we cancelled the picnic.
Although the test was difficult, she passed with a high score.
Rule 2: Independent Clause First = No Comma
If the sentence begins with the main clause and the dependent clause follows, you do not use a comma.
We cancelled the picnic because it was raining.
She passed with a high score although the test was difficult.
D. Nuances and Common Confusions
-
Since vs. Because: Since can refer to time ("I've been waiting since 5 PM") or reason ("Since you're here, you can help"). In formal writing, if your meaning is "reason," it is often clearer to use because to avoid any ambiguity.
-
While vs. Whereas: While can mean "at the same time" (He fell asleep while watching TV) or show contrast. Whereas only shows contrast and is more formal.
> The north of the country is industrial, whereas the south is mainly agricultural. -
As: The word as is a weak conjunction because it has many possible meanings (time, reason, comparison). For clarity in formal writing, prefer a more precise conjunction like while or because.
E. Reduced Adverb Clauses (Advanced Skill)
At a C1/C2 level, you can make your writing more concise by "reducing" adverb clauses. If the subject of the main clause and the subordinate clause is the same, you can often remove the subject from the subordinate clause and change the verb form.
1. With -ing
This is the most common reduction.
- Full: Before I left the house, I checked that the windows were closed.
-
Reduced: Before leaving the house, I checked that the windows were closed.
-
Full: While she was running for the bus, she fell.
- Reduced: While running for the bus, she fell.
2. With Past Participles (for passive voice)
- Full: Although it was written many years ago, the book is still relevant today.
- Reduced: Although written many years ago, the book is still relevant today.
Important: You can only reduce the clause if the subject is the same for both verbs.
* ✗ Incorrect: While running for the bus, my bag fell. (This implies the bag was running).