As I edit client documents, a common convention I see used is the “and/or” combination.
If you haven’t seen it, it’s usually used to represent multiple options, including the combining options. For example, in “Please bring cake and/or ice cream”, the speaker suggests that you can bring cake, ice cream, or cake and ice cream.
The problem with this usage is that it sounds awkward. It is particularly unwieldy when you read it aloud. The fact that it was first recorded in a legal document should be a dead give-away as to it awkwardness. Besides, it tends to make the author seem indecisive.
My personal preference is always to reword the sentence. In my example above, I might use instead: “Please bring cake, ice cream, or both.”
What do you think? Let me know in the comments below.