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Is using “and/or” recommended for formal writing, or is it frowned upon?
Alternatives to “and/or”?
Is it correct to use and immediately followed by or, or or immediately followed by and as in the following examples?
The meaning I want to say in the given examples is "You can use x or y or both".
If this is in written context you can use or/and, which should be fine.
In spoken context, it is usually understood from the context if both would be meant to be included or not eg. Tom wanted to marry Stella or Mary. We would assume, here, both is not meant. :-)
Knowing a European language, French or German may be helpful, if you plan to go on a trip to the Alps. Surely, here, knowing both wont hurt, if knowing one helps!
Usually only 'or' suffices to mean both as well, since in usual common sense and boolean logic 'or' is just that: either of the two or both. This is why the term ex-or (exclusively 'or') was invented to mean: either of the two, but not both.
and/or or or/and or both? :-) Of course +1 for you.
Commented
Feb 26, 2012 at 19:01
Using and/or is in my opinion redundant and awkward. If you want to stress that both may be chosen, say, "do you want X or Y or both?" In most cases, or is not required to be mutually exclusive, so there is no need to emphasize it. "Do you want pizza or a hot dog?" always leaves open the answer "both," or even the humorous answer "yes" (meaning the same thing).
To clearly denote that both cannot be chosen, you would use either/or: "You may choose either X or Y." Also, "which one: X or Y?" or "choose only one of X and Y." The respondent can still say "both".
If you insist on using and/or, it takes a slash, not a space. Using two conjunctions in a row doesn't makes sense. It's as awkward and incorrect as "You must could do this." Yikes!
Note that or/and has fallen into disuse in the last 30 years and many people will find it strange.
