Semicolons may be used to separate sequences of a sentence in two special circumstances.
- Long sentences with many commas
If a sentence is so long and so full of commas that it cannot be easily understood, use a semicolon to mark the most important break in the sentence.
At the university, where budget cuts have threatened programmes, students, despite warnings about disrupting classes, are occupying buildings; and the teaching and non-teaching staff, whether or not they support the student demands, are unable to enter the faculties where they work. - Long or grammatically complex lists
Use semicolons to separate long or grammatically complex items in a list, or to make them more conspicuous than they are with commas. For example, use commas with a list of persons, places or dates, but use semicolons when the items are reasons, examples or findings.
The main arguments for passing the university statutes are: their reflection of changes in higher education; the flexibility of the language used in them; and the absence of sound reasons for rejecting them. When items in a series involve internal punctuation, separate them by semicolons for the sake of clarity.
The membership of the committee was as follows: PDI, 4; PAS, 5;students, 3. However, it is often better to split a very long sentence into two separate sentences.