Correct comma usage in a list with groups

Question

I am writing a list of features, and am stuck on how to correctly handle the comma usage.

There are, essentially, "groups" within the list that are throwing me off.

I'm going to be a bit long-winded with my examples and explanation because I don't really know how to explain this problem concisely, but if you want to skip to the problem, it's the last example near the bottom!

Let's consider this test case... the items in the list are:

• Banana sales
• Orange sales
• Watermelon sales

In this case I might write something like "We offer banana sales, orange sales, and watermelon sales"

Now let's consider this list:

• Banana sales
• Banana insurance

In this case, because the items are somewhat grouped by both relating to bananas, I would write it like "We offer banana sales, and insurance"

Now to get to my problem, I want to essentially combine those two ideas for this list:

• Banana sales
• Banana insurance
• Orange sales
• Watermelon sales

So my first thought was to write something like "We offer banana sales, and insurance, orange sales, and watermelon sales" or "We offer banana sales and insurance, orange sales, and watermelon sales"

But that does not seem like it would be correct. What's the solution?

Answer 1

In a list with groups, commas can be supplanted with semicolons. This is common practice in professional writing.

Now, in your final example...

We offer banana sales and insurance, orange sales, and watermelon sales

There aren't any internal commas to supplant. It may seem clunky (it is), but it is correct. You could massage it by moving the banana noun phrase to the end...

We offer orange sales, watermelon sales, and banana sales and banana insurance.

(Banana is repeated to make it explicit that the insurance does not distribute across the list.)

A consolidating alternative which removes weak verbs could be:

We sell bananas, oranges, and watermelons, and we offer banana insurance.

An example with semicolons would look like this:

We offer banana sales, insurance, and trading; orange sales; and watermelon sales.

https://www.thepunctuationguide.com/semicolon.html

Answer 2

Firſt of all, with juſt two items in a liſt, the comma is omitted, ſo inſtead of "We offer banana sales, and insurance" it ſhould be "We offer banana sales and insurance". As for your actual queſtion, I would put either "We offer banana ſales and inſurance, as well as orange and watermelon ſales." or "We offer banana, orange, and watermelon ſales, in addition to banana inſurance." The comma before "and" in a liſt of three or more items is called the Oxford comma, and is optional in moſt writing, although ſtrongly encouraged in ſome circles and diſcouraged in others.