If the author of this sentence is not a habitual Oxford comma user, the reader doesn’t know if endogenously synthesized cholesterol, the absorption of dietary cholesterol and the reabsorption of biliary cholesterol in the small intestine is a list of three items, or if the comma separates an introductory phrase from an independent clause beginning with two noun phrases. If the reader knows the author is consistent in his use of the final serial comma, there would (should) be no confusion. The problem is the lack of semicolons, not Oxford commas!
It is simply impossible to deny that those lists would be made clearer and less awkward with an Oxford comma. These are good examples of how the consistent use of the Oxford comma can avoid temporary confusion as to the meaning of a sentence: In addition to endogenously synthesized cholesterol, the absorption of dietary cholesterol and the reabsorption of biliary cholesterol in the small intestine also contribute to the regulation of the plasma cholesterol level.
The way they are, those lists often require re-reading so our minds can perform the mental separation that the authors were too dense to provide on the page.
A comma between each pair of items in the list would put all items on equal standing regardless of length, would give each item its own slot between commas or bookending the list, would make the separation between items clear, and would make each list more symmetrical, balanced, and measured. The problem with all of those lists is that the last and/or second-to-last item is much shorter than at least one other item in the list, leading our minds to group two separate items together because of their shortness and the lack of a comma separating them. Thirteen adolescents aged 13–18 years with poorly controlled type 1 diabetes, 19 parents and 9 health-care professionals participated.The title is pretty self-explanatory: these are some rules and examples of tricky, confusing, frequently abused/ignored, or difficult-to-remember aspects of English grammar. What is necessary for ease of reading is the comma after it.Many of the example sentences are about science or medicine because I edit biomedical research manuscripts written by foreigners to improve their language and grammar to the level of native English speakers, so I’ve used their errors to teach from. That is supposed to be a list of three different treatments.
I should also note that many of these issues are more properly classified under style or usage. If that isn’t clear to you, it isn’t because you aren’t a scientific researcher and aren’t familiar with the terminology; it’s because the authors left out a necessary comma.
It’s true that “if needed” could be surrounded by commas, but this is not necessary.
I’d wager that few people would clearly understand this sentence on first read without the Oxford comma but that many people would (scientists, anyway) with it.
I don’t know about you, but that sentence was temporarily confusing the first time I read it, and today when I browsed my ever-growing list of Oxford comma–needing sentences to find some more good ones to add to this guide, this sentence initially confused me again.
In such cases it is almost never necessary to separate the items of the list with semicolons.
That is a ridiculous sentence that is difficult to follow because of the lack of Oxford commas before the last two ors. ” No, that sentence is perfectly clear with Oxford commas but no semicolons: As is made clear by the Oxford commas, the only individual item in that list that contains commas is the last one.