How to use a semi-colon correctly
The most common use of the semi-colon is to join two independent clauses without using a conjunction like and.
A semi-colon is only followed by a capital letter when the next word is a proper noun or an acronym.
We should leave early; Dublin is really busy after 5pm.
1. Semi-colons connect related independent clauses
A semi-colon is used to join two closely related independent clauses (the group of words before the semi-colon have to form a complete sentence, and the group of words after the semi-colon also have to make up a complete sentence). The second sentence must be an implication of the first sentence or have a logical connection to it.
Jim is really fit; he swims 2km every day.
The advert is popular; it has been watched more than a million times on YouTube.
Roads are closed around the area due to flooding; the police are advising people to avoid travelling by car.
2. Delete the conjunction when using a semi-colon
Conjunctions can also link two independent clauses (e.g. and, but, or), but we don’t use a semi-colon and a conjunction together.
Jim is really fit because he swims 2km every day.
Jim is really fit; he swims 2km every day..
3. Use semi-colons in a list
We use semi-colons to divide the items of a list if the items are long or contain internal punctuation. In these cases, the semi-colon helps the reader to notice the divisions between the items more easily.
John will visit the following cities on his world tour: London, England; Dublin, Ireland; Aberdeen, Scotland; Lisbon, Portugal; Seoul, Korea; and Taipei, Taiwan.
My favourite things to do after work are to go to the beach and jog; make meals using recipes I find online; relax on the sofa and drink some wine, whiskey and beer; and text my friends on WhatsApp.
Note that we can use a conjunction (and) after a semi-colon here because it is the end of the list.