“Two plus two {make/makes} four.”

Two plus two make four.
Two plus two makes four.

What verb should I use there, make or makes?

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Answered here: english.stackexchange.com/questions/9053/… – relaxing Mar 30 '14 at 16:52
Duplicate as noted by @relaxing – CoolHandLouis Mar 30 '14 at 17:04
@CoolHandLouis We can't close posts here as duplicates of posts there. – snail plane Mar 30 '14 at 17:43
I say "two plus two is four" (when talking about arithmetic) rather than "two plus two are four". Just as I say "two is a prime number" and not "two are a prime number". – GEdgar Mar 30 '14 at 18:25

You will occasionally hear people employ plus as a conjunction, and even see people write it. But here it is unambiguously a mathematical operator, and the phrase two plus two is unambiguously a single mathematical expression.

Two plus two makes four.

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A bit of googling shows that it is at least somewhat ambiguous whether you conjugate the singular operation or the collective operands... – relaxing Mar 30 '14 at 16:57

You will find both of these used, but I think you'll find is used even more often than either make or makes. Here's an Ngram:

As for why both are used, that's not hard to figure out. If the subject is singular, the verb makes is used:

The baker makes a cake.

If the subject is plural, the verb make is used:

The bakers make a cake.

So, if the subject is two plus two, that could be considered singular or plural, depending on how you parse it:

• It could be plural, because we are talking about a quantity of four
• It could be singular, because we are talking about a single math problem with one answer

Since either argument is a valid argument, you'll see it get used both ways:

Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
(George Orwell, 1984)

Well, I'm not a star in the mathematics department, but I do know that two plus two makes one less than five and one more than three.
(Tennessee Williams, The Gnädiges Fräulein)

And let's not forget:

Well, one and one is two / Six and two is eight / Come on baby don't ya make me late...
(The Blues Brothers, Sweet Home Chicago)

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Two plus two "makes" four. The addition "makes" four.

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I will take the contrarian view and point out that many people say

Two plus two make four

In fact, you will also hear

Two and two make four

The reason: there are two subjects with a plural verb.

The number 2 and the number 2 make 4.

That is why people say it like this. This has nothing to do with being a mathematical formula and everything to do with how English works.

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As far as I am concerned, there are independent sittings of two subjects of the same nature; however, the word independent speaks about singular, and 3rd person singular subject always follow the "addition of" with its main verb:

Two plus two makes four

Here the subjects are repeated, not plural and the object '4' is a single number despite being compound.

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