# Are these plural or singular?

I was surprised when I heard zero is plural, and even 1.00001 is plural.

Then, what about following numbers ?

(1) 1.00

which means the value measured between 0.995-1.004, having possibility that it was exactly 1.

(2) 0.99999.....

which is mathematically equal to 1. Also, are others that are mathemattically equal to 1 than this, treated completely same as 1?

(3) -1

Is this singular? Or negative numbers are generally plural?

(4) i = square root of -1

I know it's weird to count things with imaginary numbers, nonetheless, if you were to count, which form, plural or singular, would you be to use?

That's it.

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Whatever in the world do you mean? This is about English grammar, not mathematics. Define "is plural", please. And give evidence that what you "learned" is in fact true. – John Lawler May 28 '12 at 3:54
@JohnLawler I used "is plural" to mean that the word will be followed by plural noun or unit like "0 degrees" "3 dollars" and so on. So I should have said "is followed by a plural noun" instead. Sorry if my words didn't make sense. – takuma7 May 28 '12 at 4:23
@TaKUMA7 seemed clear to me – Dodgie Jan 5 '14 at 18:09

It has less to do with the actual number, and more to do with how the number is said or written.

Singular nouns:

Any time the number is "one", or a fraction with "one" in the numerator, the result is singular. This also applies to negatives. See Is -1 singular or plural?

• One apple
• 1 apple ("one apple")
• Half an apple
• One half of an apple
• 1/2 apple ("one half apple" or "half of an apple")
• 1/4 apple ("one quarter apple" or "one quarter of an apple" or "one fourth of an apple")
• -1 volt ("minus one volt", "negative one volt")

Plural nouns:

Any decimal number, including 1.0, is plural. See Should we use plural or singular for a fraction of a mile?

• 1.0 apples ("one point zero apples", "one point oh apples")
• 0.5 apples ("zero point five apples", "oh point five apples")

Complicated cases:

Fractions with numerators larger than one can be handled both ways. This also applies to percentages. The plural form is used for countable objects, and the singular form is used for non-countable objects. See Is two-thirds plural?

• 2/3 of the people are here. (We are counting people.)
• 2/3 of the soda was left over. (We are not counting soda.)
• 75% of the computers are broken. (countable)
• 75% of the rice was eaten. (not countable)

Complex and imaginary numbers:

Complex and imaginary numbers only appear in technical contexts. I can only think of examples with units, for example:

• 5.7+3.1j kΩ at 500 Hz
• -1.0+0.9j mV at 10 kHz

Note that engineers usually use "j" instead of "i" to avoid confusion with I, the symbol for current. Mathematicians use "i".

In technical contexts, quantities for should be written with numerals and units should be written with abbreviations, which do not take plural. So "5 V" is okay, but "five volts" is only okay in non-technical contexts.

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Wow, thank you for your immediate and very well-organized answer! Now it's clearer for me. By the way, as to the last example, the complex and imaginary one, how you pronounce when 0 + 1j mV ( so, just 1j mV)? – takuma7 May 28 '12 at 4:36
Wow, that was a good answer. I don’t know why we say “⁹⁴⁄₁₀₀ of an apple” or “94% of an apple”, and those as subjects would take a singular verb, while “0.94 apples” takes a plural verb, yet certainly we do. Recipes do use “2 cups” vs “¾ cup”, though. I get they’re using those as units, like “2 T. salt” for two tablespoons of salt, or “4 t. crushed garlic” for 4 teaspoons of the stuff. – tchrist May 28 '12 at 4:42
@TaKUMA7: I think I would pronounce it as either "zero plus one jay millivolt" or "zero plus one jay millivolts", but it's very rare to say it out loud. If at all possible, I would avoid saying it out loud at all. (For example, if you are presenting a research paper, you can leave the data on the slides and not read it out loud.) – Dietrich Epp May 28 '12 at 4:57
@tchrist: Hm, I wonder if the convention is just different in recipes. I would definitely read a recipe aloud as "two cups flour" and "three-quarter cup sugar". – Dietrich Epp May 28 '12 at 5:02
@DietrichEpp Really? That sounds quite wrong to me. I would say "Two cups of flour and three quarters of a cup of sugar" and I don't think I've ever heard it said any other way. Is the usage that you describe common in your region? – user16269 May 28 '12 at 8:17

It all depends on how you say it, for example 1.00 is plural if read as "one point o o", but is singular if read as "one". In cases of fractions, English rules are not so concrete. 1/2 ft could be read as "one half of a foot" or "one-half feet", or "one half-foot". All 3 are grammatically correct. It doesn't actually matter on the value of the number, but how the number is being interpreted.

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