61

Donald Knuth, that doyen of computer science, says in Art of Computer Programming, Vol 2.: Detail-oriented readers and copy-editors should notice the position of the apostrophe in terms like "two's complement" and "ones' complement": a two's complement number is complemented with respect to a single power of 2, whereas a ones' complement number is ...


53

The most useful rule — and the most general and the easiest to remember — is simply that you add ’s whenever you actually say an extra /əz/ at the end when forming the possessive, compared with how you say the non-possessive version. Let your own ear be your guide. That’s all there is to it. No fancy rules full of exceptions. Just your own ear (as a native ...


45

The fourth example is the correct interpretation of day's, but with two things to keep in mind. First, in your conclusion you flipped the words around incorrectly*; the journey "belongs to" the day, not the other way around. You could re-write the sentence as: The house is a journey of a full day from here. Second, while the journey is "of a day," this ...


41

It's called a "transferred epithet"- the possessive case is incidental, as in... I had a good night's sleep: The good sleep was mine to enjoy, but it is attributed to the night it happened. He put in a honest day's work: The quality or extent of work belonged to the doer, but it is attributed to the day.


35

The answer lies in the history of how apostrophes have been used, and how this has then changed: A Brief, but not that Brief, History of the Apostrophe in English There’s a myth that the apostrophe is only used for elision. It’s a pretty useful myth, because believing it is unlikely to lead you into mistakes if you are using the most popular styles today, ...


29

As few people are addressing the '"more scientific™" sources' bit of the question, it should be pointed out that there are a number of English style guides out there, practically all of which should cover the topic of forming possessives with apostrophe-s (as it's a frequent issue even with native speakers). You should be able to find copies of at least one ...


25

There are a few limited cases for which an apostrophe is not used to indicate possession. For example, if you're referring to something belonging to it or her, the correct form is its or hers, with no apostrophe. Such an exception does not apply to column. If you want to refer to the width of a particular column, you would say the column's width. In the ...


22

The strongest endorsement that I could find from a UK English source in favor of using 's after singular nouns of any kind to indicate possession is this brief treatment from The Oxford Guide to Style (Oxford University Press, 2002): 5.2.1 Possession Use 's after singular nouns and indefinite pronouns that do not end in s: [Examples:] the boy's ...


21

A piece of advice here from someone who did a CS Master's thesis himself: You don't. You write it the way they want it written. Consider it like a house style guide. The rules in style guides aren't the only way to do proper English; just the way they do it there. Your goal here is to get a CS Master's, not a Booker Prize. Look at it this way: Your advisor ...


19

T. O. Churchill, A Grammar of the English Language (1823) identifies two somewhat surprising culprits as being responsible for the deplorable rise of the apostropheless its: printers, and English speakers who inexcusably use of the wrong contraction for "it is." Here is Churchill's argument: The word it's in particular, is now generally robbed of ...


18

My answer focuses on the header question about decades—which is the question that most readers will probably expect to find answers to here. With regard to decades expressed in numerals rather than spelled out in letters, some style guides recommend omitting an apostrophe, while others recommend including it. For example, from The Chicago Manual of Style, ...


17

From Charles Darwin's Origin of Species OR THE PRESERVATION OF FAVOURED RACES IN THE STRUGGLE FOR LIFE. From the First Edition, 1859 One of the most remarkable features in our domesticated races is that we see in them adaptation, not indeed to the animal's or plant's own good, but to man's use or fancy. […] How fleeting are the wishes and efforts of ...


15

Since you are talking about multiple others ("...the lives of others"), then the apostrophe comes after the s. having an impact on others' lives


15

It would depend on what you meant. If you mean the Brazilian army was short of ammunition, then you would write the Brazilian Army's ammo supply is low. But if you were referring to an army that is not the Brazilian army, but instead owned or run by a particular Brazilian (perhaps an army of toy soldiers, or an army of mercenaries), then the Brazilian's ...


14

Since this is a question about acronyms, and the Federal Government's bureaucracy is notorious for using acronyms, I decided to look up the answer in the United States Government Printing Office (GPO) Style Manual (2000). Rule 8.11 of the GPO Style Manual states: "While an apostrophe is used to indicate possession and contractions, it is not generally ...


14

According to the MLA Handbook, section 2.2.7: A principal function of the apostrophe is to indicate possession. The apostrophe is also used to form ... the plurals of the letters of the alphabet (p's and q's, three A's). So, according to MLA at least, these logos have it right.


13

Each other is singular, so the correct possessive is each other's. Edit: I found some controversy on this on the web because each other implies that there are multiple people involved, hence people think it is plural and should be written each others'. This, however, is wrong as each is always singular.


13

Wilson Follett, Modern American Usage (1966) vigorously opposes applying a possessive 's to an inanimate thing (as in "this blog's existence"), calling such possessives "false" and concluding that "we must stick to the ancestral rule which, with a few exceptions, reserves possessives in 's for ownership by a person." Shoe's ...


12

Bryan Garner, Garner's Modern American Usage, second edition (2003) offers the following discussion of how to handle possessive proper names ending in -s: POSSESSIVES. A. Singular Possessives. To form a singular possessive, add 's to most singular nouns—even those ending in -s, -ss, and -x (hence, Jones's, Nichols's, witness's, Vitex's). ... There are four ...


12

Apostrophes can be used to show omission of letters. It can also be used to form plurals of lowercase letters. Consider if, after abbreviating "Athletic(s)" to "A", you wanted to refer to the team in a sentence: The As won the game. One could easily misread the team name as the word "as", though that makes the sentence ungrammatical. The apostrophe clears ...


12

"A day's work" typically means the amount of work one would normally do over the course of a day. There is no objective measure of this as the amount of work would vary by person and by job. For most people, though, it would not be possible to do "a day's work" between waking and breakfast, so in the Dickens quote the phrase is probably being used for ...


12

The 's on the day's is possesive in your case - but see @Simha's answer More time examples Three months' experience One month's experience Today's appointment In two days' time A year's worth of magazines


12

A backtick would be my last recommendation. A straight single-quote is acceptable, and a curly close quote can be substituted as an improvement. In other words, of these three: It`s common sense. . . . It's common sense. . . . It’s common sense. . . . I would avoid the first, accept the second, and consider the third to be superior to the other two. One ...


12

Danger! Wasp Nests! No apostrophe in this case, because there is no possessive*. Here "Wasp" is an attributive noun, and therefore can be in the singular form even though there is more than one nest and there isn't necessarily just one wasp associated with each nest. "Nests" is the ordinary plural form of "nest." Nothing here should bother a well-educated ...


11

My copy of Practical English Usage, 2nd Edition (Michael Swan, 1995) says this: Apostrophes are used in the plurals of letters, and often of numbers and abbreviations. He writes b's instead of d's. It was in the early 1960's. (OR ... 1960s.) I know two MP's personally. (OR ... MPs.) Using Amazon's Search Inside The Book I can see that ...


11

I just stumbled upon this picture (from William Haefeli) which illustrates: the common usage of "Mother's Day" (ie, the day of your Mother, or anyone's Mother, as in one Mom) the... other case ;)


11

According to an earlier answer to another question, David Crystal's book The Fight for English: How language pundits ate, shot, and left says that lack of apostrophes in possessive pronouns was due to forgetfulness on the part of 19th century printers and grammarians: Its is just as possessive as cat’s, but it doesn’t have an apostrophe. Why not? Because ...


11

Michael Swan writes in Practical English Usage (2005.441-2) "With nouns which are not the names of people, animal, countries, etc, 's is less common, and a structure with a preposition (usually of) is more common." However, he adds "... both structures are possible in some expressions. [..] Unfortunately it is not possible to give useful general rules in ...


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