Subordinate clauses in writing are one of the most powerful tools in the writer’s grammatical repertoire, and one of the least discussed in practical terms. Most writing advice that touches on grammar does so in the negative — avoid passive voice, vary sentence length, don’t use too many subordinate clauses. The positive account — what subordinate clauses in writing actually do when used deliberately — is less often given. This is a gap worth filling, because the decision of when to subordinate a clause and when to let it stand alone is one of the decisions that most directly shapes how an argument moves and how a reader experiences it.
What Subordinate Clauses in Writing Actually Do
A subordinate clause is a clause that cannot stand alone as a sentence — it depends on a main clause to complete its meaning. Although the evidence was strong is a subordinate clause. Although the evidence was strong, the argument was not convincing is a complete sentence, in which the subordinate clause modifies the main clause.
The relationship between a subordinate clause and its main clause is not neutral. Subordination establishes hierarchy — it tells the reader that one piece of information is primary and another is secondary, that one thing is the main point and another is the context in which the main point should be understood. This hierarchy is one of the most important kinds of information a writer can communicate, and it is communicated grammatically rather than explicitly.
Compare two versions of the same information. The evidence was strong. The argument was not convincing. Two independent clauses, equal in grammatical weight, each asserting its content without indicating the relationship between them. The reader must infer the relationship — that the strength of the evidence makes the weakness of the argument surprising, or that the two things are in tension. Although the evidence was strong, the argument was not convincing. Now the relationship is explicit: the strength of the evidence is the context; the weakness of the argument is the point. The subordinate clause does not just carry information — it tells the reader how to weight it.
What Subordinate Clauses Signal
Different subordinating conjunctions signal different relationships — and choosing among them is one of the most precise things a writer using subordinate clauses in writing can do.
Although and even though signal concession — the subordinate clause acknowledges something that might be expected to contradict the main clause but does not. Because signals cause — the subordinate clause explains why the main clause is true. If signals condition — the main clause is true only under the circumstances the subordinate clause describes. When and while signal time or simultaneity — they place the main clause in a temporal relationship with the subordinate clause.
Each of these relationships can be expressed less precisely through coordination — and, but, so — or left implicit and expected to emerge from juxtaposition. The writer who uses subordination rather than coordination is choosing precision over simplicity. They are telling the reader exactly how the pieces relate rather than leaving the relationship to be inferred.
This precision comes at a cost: complexity. A sentence with a subordinate clause requires the reader to hold more in mind than a simple sentence — they must track the main clause, the subordinate clause, and the relationship between them. This is a cost worth paying when the relationship is important and the precision is necessary. It is a cost not worth paying when the relationship is obvious and the complexity is simply weight.
When to Use Subordinate Clauses in Writing
The decision to use subordinate clauses in writing is a decision about what the reader needs to understand about the relationship between two pieces of information.
Subordination is right when the relationship is not obvious — when the reader, left with two independent clauses, would not reliably infer the relationship the writer intends. The evidence was strong. The argument was not convincing. A reader might read these as simply two facts, rather than as a tension the writer considers significant. The subordinate clause makes the tension explicit.
Subordination is also right when one piece of information is genuinely secondary — when the writer wants the reader to register it but not treat it as equal in importance to the main clause. Background information, qualifications, concessions — these are often best expressed as subordinate clauses, because they occupy less of the reader’s attention in that form than as independent sentences.
Subordination is wrong when used as a default — when the writer routinely embeds clauses rather than thinking about whether a given piece of information warrants the reduced emphasis that subordination produces. Some information presented as subordinate is actually important, and the subordination is hiding that importance. Some sentences that run long through multiple layers of subordination would be clearer as two or three shorter ones, because the reader cannot hold the whole structure in mind long enough to process its content.
Subordinate clauses in writing do something that independent clauses cannot: they tell the reader how to weight what they are reading. They communicate relationship and hierarchy, not just content. A writer who uses them deliberately — choosing subordination when the relationship needs to be explicit, choosing independence when two things are genuinely equal — is writing with a precision that grammar instruction rarely describes as a positive capability, but which is one of the most available and most underused tools in the craft.
The clause that is subordinate is not lesser. It is differently important — and the difference is the writer’s to decide.
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