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4 Commonly Misused Plurals: 
Don’t Accidentally Make Your Audience Cringe

English is a concoction of words that hail from many sources. Ever evolving, some grammar, punctuation, and usage rules can be confusing. For example:

The plural of ox is oxen, but the plural of box, is most definitely not boxen.

01-20 September Iris
Singular = iris, plural = irises or iris or irides, depending

I agree with Grammar Girl about being gentle and friendly with the rules. Let’s forgive others and ourselves for making common mistakes, but let’s also see if we can avoid them.

Here are four questions about words I commonly hear misused in performance improvement circles. You can find the correct answers and explanations below.

  1. When talking about Evidence-Based Practice (EBP) or being data-driven in our approach, it’s easy to stumble over the word data. Which is correct?
    • The most recent data show that…
    • The most recent data shows that…
  2. Let’s say that we are talking about a whole set of courses for the Business School at the local college. Which is correct?
    • The curriculum includes…
    • The curricula includes…
  3. Let’s discuss how we’re going to deliver instruction to our students. Which of the following is correct?
    • As media go, video offers a lot of flexibility
    • As mediums go, video offers a lot of flexibility
  4. Let’s say there are two upcoming meetings for exchanging views on gamification. Which is correct?
    • The forums will be held downstairs.
    • The fora will be held downstairs.


  1. Data is Plural. Researchers and people in scientific disciplines (including the social sciences) usually say “the data show….” Datum is the singular form. The plural form is data, so we say, “The data were collected.”
    Data Can Be Singular. You may often hear people refer to data as a singular noun. For nontechnical audiences, data is often used as a mass noun, like information, which is singular.
    What to Do? For more technical audiences and publications, use data as a plural noun. If your organization or publication has a style guide, that’s helpful. If not, consider your audience. Above all, be consistent.
  2. Curriculum Is Singular. Correct = “The curriculum includes….” We could also say, “The English curriculum is large and varied.” When we have multiple sets of courses, the plural is curricula. In that case, “The science disciplines have diverse curricula.”
    Note: Some people have a habit of calling each course a curriculum. However, a curriculum is defined as a set of subjects, so it is not usually just one course. Curricula are multiple sets of courses, like the management and engineering curricula at a corporate university.
  3. Don’t Accidentally Be Occult. Medium is singular. Media is plural. Mediums are people who communicate with the spirits of the dead. Correct = “As media go, video.…”
  4. Don’t Accidentally Time Travel to Ancient Rome. Forum is singular. Forums is plural. Fora refers to public squares or marketplaces in ancient Rome. Correct = “The forums will be….”

I’ve heard these four terms misused many times in the performance improvement world. It’s easy to cringe a little when that happens.

If you are in this field, it’s a good idea to commit the singular and plural forms of these four terms to memory.


Site | Grammar Girl

Quiz | Can You Identify the Plural of These Tough Words?

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