Last week, Sir Richard Branson stated that he was "jealous" of Elon Musk's success in building spacecraft. When CNN reported the story, it put the word "jealous" in quotes, possibly because Branson had misused the word.

If so, then, in a way, CNN was casting a bit of shade on Branson's vocabulary. That kind of grammar snobbery is quite common, which is a good reason to sort out your Ps and Qs. With that in mind, here are seven common words and phrases that most people get wrong:

1. "jealous" vs. "envious"

Back to Branson's remark about his feelings towards Musk, "jealousy" only refers to three-sided "affairs of the heart." For other situations between two individuals, the correct term is "envy."

Therefore, while Sir Richard Branson might be envious of Elon's Musk's success in spacecraft, he would only be jealous if Musk were, for example, dating Branson's girlfriend.

2. "Bill Gates'" vs. "Bill Gates's"

In English, the possessive of every singular noun--even singular nouns that end in "s"--is formed by "apostrophe s" with one curious exception (which I'll get to in a moment). Thus "Joe's bike" and "Jess's bike" are both correct but "Jess' bike" is incorrect.

The incorrect form comes from a misinterpretation of another rule, which is that the possessive of every plural (not singular) noun that ends in an "s" is formed by a simple apostrophe. Thus "the crowd of angels' wings" is correct because "angels" is a plural.

There is, however, a weird exception to this rule. When referring to personages in the Bible whose name ends in "s," the plural is formed by adding just an apostrophe. Hence "Jesus' words" is correct while "Moses's tablets" is incorrect.

This rule apparently exists because at one time it was considered sacrilegious to alter "holy" names. This taboo dates back to the time when people believed that words were magically linked to whatever they described rather than just arbitrary labels created through conventional usage.

Therefore, if you write "Bill Gates' legacy" rather than "Bill Gates's legacy," you're implying that he's not just a billionaire but a Biblical prophet.

3. "shall" vs "will"

In accepted usage, "shall" and "will" are interchangeable; both are used to express the future tense. Thus, for most people, "I will go" and "I shall go" are equivalent. However, the correct usage is as follows:

  • I shall...
  • You (singular) will..
  • He will...
  • We shall...
  • You (plural) will...
  • They will...

However, if you wish to add emphasis and determination to the verb, you use the reverse:

  • I will...
  • You (singular) shall...
  • He shall...
  • We will...
  • You (plural) shall...
  • They shall...

The following conversation illustrates the difference:

  • Jim: "I shall go to the store."
  • Joe (disbelieving): "No, you won't."
  • Jim (emphatically): "Yes, I will!"

4. "an history" vs. "a history"

Most people know that the article "a" turns into "an" when it proceeds a word that begins with a vowel, thus "a bird" and "an owl" are both correct but "a owl" is not.

However, if a word begins with something called an "aspirated h," it's also preceded by "an."

An "aspirated h" is an "h" that's soft (like "hymn") rather than fully pronounced (like "hate"). Thus "an history" (pronounced "an istory") is correct while "a history" (pronounced with a hard "h") is not.

5. "octopuses" vs. "octopi"

OK, I admit that the word "octopus" doesn't come as much in business conversations as the word "squid" (usually preceded by "vampire"), this mistake is so common that I can't resist mentioning it here.

Most people know that English words that end in "us" form their plural by replacing the "us" with an "i." Hence the plural of "cactus" is "cacti."

However, this is only true if the word comes from the Latin. If a word that ends in "us" comes from a different language, such as Greek, it forms its plural in the normal way for English words that end in "s"--by adding "es" to the end.

Thus--and I kid you not--the correct plural of "octopus" is not "octopi" but "octopuses." Octopi, though, has been misused so frequently that it's now accepted usage. But it's still not correct, strictly speaking.

BTW, the plural of "octopus" in Greek is "octopodes."

6. "datum" vs. "data"

Words end in "um" that slipped into English directly from the Latin language form their plural by replacing the "um" with an "a." Thus, "datum" is a singular noun whose plural is "data."

Therefore, when you're talking about a single piece of information as a noun it's a "datum" not "data." So "each datum is stored at this physical address" is correct while "each data is stored at this physical address" is incorrect.

Some people get around the seeming awkwardness of "datum" by using "data" as an adjective, as in "each data point is stored at this physical address."

Words ending in "um" that did not come directly from Latin, do not form their plurals in this say. For example, the word "vacuum" came into English from the Dutch language, so the plural of "vacuum" is "vacuums" not "vacua." Although vacuous people might not know that.

7. "agendas" vs. "agendae"

A number of words that end in "a" that originally came from Latin form their plurals by replacing the "a" with "ae."

Hence, even though most spellchecking programs get this wrong, the correct plural of "amoeba" is "amoebae" not "amoebas." Other common English words that follow this rule are "encyclopedia," "alumna," "hyena," "larva," "formulua," "corona," "nebula," and "vertebra."

However, even though the word comes from Latin, the plural of "agenda" is not "agendae" but "agendas."


Because "agenda" is already plural. The original word--no longer commonly used--was "agendum" which referred to a single item on a list. An "agenda" was a collection of more than one agendum (following the same rule as datum-data.

Therefore, if you have more two of those lists, you have two "agendas" rather than two "agendae."

BTW, "pajamas" comes from the Arabic. There is no singular noun "pajama" (it's an adjective) but if there were, the plural would be "pajamas" not "pajamae." Just thought you'd want to know.

Published on: Feb 21, 2018