How to see it
A clause has a verb and someone or something doing it. A main clause makes sense on its own: the road was closed. A subordinate clause starts with a word like because, although, when, if or unless. It cannot stand alone. And, but, so and or are different. They join two main clauses that are equal. So ask: can it stand on its own?
A worked example
It has a subject and a verb. But because promises a reason for something, and the something never comes. Add a main clause. Because the river had flooded, the road was closed. Now it is a sentence.
The common mistake: a subordinate clause left on its own as a sentence
The trap is a subordinate clause on its own, with a full stop. Although it was raining. It looks like a sentence, but although leaves you waiting. Join it to a main clause.
Try one
Which of these is a complete sentence?
- AWhen the bell rang.
- BAlthough we were tired.
- CIf you finish early.
- DWe kept walking until dark.
- EUnless the bus comes soon.
Show the answerHide the answer
Right: D, We kept walking until dark.
We kept walking makes sense on its own. Each of the others leaves you waiting.