I recently shared an extract from Advanced Writing Skills covering how we use commas to separate clauses (which you can read here). Another useful function of commas in complex, or even just slightly more complicated sentences, is when we use commas around additional information. To cover this, I’ve got another extract from the book below, with some extra information on how this can affect word order.
Additional information may be added to sentences separated by what can be called parenthetical commas. These behave the same way as parentheses. The information between two commas may be considered additional, and removing it should not affect the meaning of the sentence. Such information can be added for extra detail or commentary, and can come in the form of a few extra words or entire phrases or clauses:
- The dress was unsuitable.
- The dress, old and smelly, was unsuitable.
- The dress, would you believe, was unsuitable.
- The dress, old and smelly through years of use and no particular care for its upkeep, was unsuitable.
Parenthetical commas may also be used to move information from elsewhere in the sentence:
- Kylie prepared to watch the fireworks with great excitement.
- Kylie, with great excitement, prepared to watch the fireworks.
- Kylie prepared, with great excitement, to watch the fireworks.
If you don’t put commas around such information, the sentence can become confusing:
- The dress of course was unsuitable. (This makes the dress appear to belong to course, which does not work.)
- Kylie with great excitement prepared to watch the fireworks. (This makes the excitement sound like part of Kylie’s name.)
When we do use commas in this way, word order can become very flexible. The various components of sentences which you can learn about through studying correct word order can, realistically, be moved to any location you choose, typically to add emphasis. This is a powerful technique, but one you need to be careful with, as we with typical word order for a reason – it sounds more natural and fluent, and moving sentence components can be confusing.