Subordinating Conjunctions Guide: Rules, Examples, Punctuation, Quiz & FAQs
A subordinating conjunction introduces a dependent clause and links it to a main clause, signaling relationships such as cause (because), contrast (although), condition (if), time (when), and purpose (so that). Subordination lets you control emphasis and logic: the main clause carries the headline; the dependent clause supplies context.
This intensive guide explains definitions, a category-based list with examples, comma rules, tricky look‑alikes (since, as, while), common mistakes, an interactive quiz, and FAQs. For the companion guide on equal links, see coordinating conjunctions.
See also: Linking Words • Conjunctions • Coordinating conjunctions • Transition words
What Are Subordinating Conjunctions? (Definition & Role)
Subordinators mark a relationship and determine the word order of the clause they introduce. They can show cause (because, since, as), contrast (although, though, even though, whereas, while), condition (if, unless, provided (that), as long as, in case), time (when, while, before, after, until, since, once, as soon as),purpose (so that, in order that, lest), result (so … that, such … that), comparison (than, as … as), or manner/place(as if, as though, where, wherever, the way).
Coordination joins equals; subordination creates hierarchy. For a clean contrast with FANBOYS, compare the sentences in the next section.
Coordinating vs. Subordinating Conjunctions (The Clean Contrast)
Coordinating: “I was tired, so I left.” (two independent clauses with a comma.)
Subordinating: “I left because I was tired.” (dependent clause + main clause; no comma.)
Commas: When the dependent clause comes first, use a comma: “Because I was tired, I left.” When it comes after, omit the comma in most cases: “I left because I was tired.”
Subordinating Conjunctions by Function (with Examples)
| Function | Common Subordinators | Example |
|---|---|---|
| Cause | because, since, as, in that | We stayed inside because it rained. |
| Contrast / Concession | although, though, even though, whereas, while | Although it was costly, we renewed the contract. |
| Condition | if, unless, provided (that), as long as, in case, whether | We’ll start if everyone is ready. |
| Time | when, while, before, after, until, since, once, as soon as | When the bell rang, the class ended. |
| Purpose | so that, in order that, lest | We trained extra so that we could finish faster. |
| Result | so … that, such … that | The test was so easy that everyone passed. |
| Comparison | than, as … as, as if, as though | She runs faster than I do. |
| Place / Manner | where, wherever, the way | Place the icons where users expect them. |
U.S. Punctuation & Word Order with Subordination
- Comma when the dependent clause comes first: “Although it rained, we played.”
- No comma when the dependent clause comes second (most cases): “We played although it rained.”
- Don’t double-mark contrast: Avoid “Although it rained, but we played.” Use one marker only.
- Because vs. because of: because + clause; because of + noun phrase.
- So that: purpose (may allow can/could) vs. result (so … that pattern). Choose by meaning.
- In formal writing, prefer because over causal since where time confusion is possible.
Tricky Pairs (Disambiguation & Register)
Since vs. Because
Use because for cause; reserve since for time unless context is unmistakable.
While: time vs. contrast
While can mean “during the time that” or introduce contrast like whereas. Pick the clearer option in formal text.
As: cause, time, or manner
If ambiguity arises, rewrite with because/when or re-order the sentence.
If vs. Whether
If sets a condition; whether introduces alternatives. “Let me know whether you agree.”
In case vs. If
In case = “as a precaution.” Not interchangeable with conditional if.
Even though vs. Although vs. Though
Even though adds emphasis; although is formal/neutral; though is slightly more conversational.
Common Mistakes (and Quick Fixes)
| Mistake | Bad Example | Fix |
|---|---|---|
| Comma misuse | Because it rained we stayed. | Add comma when dependent clause comes first: “Because it rained, we stayed.” |
| Double markers | Although it rained, but we stayed. | Use one: “Although it rained, we stayed.” |
| Because vs. because of | We canceled because of it was late. | “because” + clause → “We canceled because it was late,” or “because of” + noun → “because of the hour.” |
| If vs. whether | Tell me if you agree (two alternatives implied). | Use “whether” for alternatives: “Tell me whether you agree.” |
| Purpose vs. result | We trained so that everyone passed (result). | For result, use “so … that”: “We trained so hard that everyone passed.” |
Editing Tips for Subordination (Clarity & Emphasis)
- Put new or contrastive info in the main clause; background in the dependent clause.
- Avoid clause stacking (multiple subordinators) unless the logic demands it.
- Prefer concrete heads: turn strings like “because of the fact that” into “because.”
- Read aloud to catch awkward stress when the dependent clause is long and fronted.
Interactive Quiz: Choose the Right Subordinator
Fill in or choose the correct subordinating conjunction. Click to reveal answers.
- We left early, ___ the forecast warned of ice. (cause)
Answer
because
- ___ it was late, the library was still crowded. (contrast)
Answer
Although / Though / Even though
- We’ll start at noon ___ everyone arrives. (condition)
Answer
if
- Call me ___ you land. (time)
Answer
when / as soon as (context)
- We added examples ___ readers could apply the idea. (purpose)
Answer
so that
- She kept quiet ___ she knew the answer. (contrast)
Answer
although / though / even though
- Take an umbrella ___ it rains. (precaution)
Answer
in case
- He stayed longer ___ finish the report. (purpose; formal)
Answer
in order to finish the report (note: this uses an infinitival purpose form)
FAQs
- What are subordinating conjunctions? — See the definition above.
- What are 10 examples? — Because, although, if, unless, when, while, since, whereas, even though, as soon as.
- Do I need a comma with because or although? — Use a comma when the dependent clause comes first.
- What is the difference between subordinating and coordinating conjunctions? — See the contrast section.
- When should I use since vs because? — Prefer because for unambiguous cause.