Language
Punctuating complex sentences
Place the commas, semicolons and periods that a sentence of more than one clause needs.
Once a sentence holds more than one clause, punctuation stops being decoration and starts doing structural work. It shows the reader where one clause ends and the next begins — and a reader who has to work that out twice in a paragraph gives up on the paragraph.
Subordinate clause first — comma
Although the road was flooded, the bus arrived on time. When a clause beginning with although, because, when, if, after or since comes first, close it off with a comma before the main clause starts.
Subordinate clause last — usually no comma
The bus arrived on time although the road was flooded. The same two clauses, the other way round, and the comma is no longer wanted. The reader can already see where the main clause ended, because the joining word says so.
The comma splice
The rain stopped, the match began. Both halves could stand alone as sentences, and a comma is too weak to hold them together. Three repairs: a period, a semicolon, or a joining word after the comma — the rain stopped, and the match began.
The semicolon
The lamps were still burning; nobody had thought to switch them off. A semicolon joins two complete sentences whose meanings lean on each other. Test it by replacing it with a period: if both sides still work, the semicolon is allowed.
The colon
The kit held four items: a torch, a whistle, a bandage and a spare key. Everything before a colon must already be a complete sentence. Everything after it explains, lists or expands what came before.
Worked example
Punctuate: "After the storm passed we went down to the shore the boats had all been dragged up the beach."
Find the opening subordinate clause: "After the storm passed".
It begins with after and cannot stand alone, so it takes a comma at its end.
Try it together
Punctuate one sentence, one decision at a time.
The sentence is: Although the train was late we caught our connection it was the last one of the day. Answer each step with a single word.
1.The sentence opens with a subordinate clause. Write the last word of that clause — the word a comma belongs after.
Have a go
Which version is correct?
Ready to practice?
Eight questions on what you have just read. Nothing is timed, and you can play as many times as you like.