The Dutch apostrophe: auto's, 's ochtends, Anna's

The apostrophe (de apostrof) is the raised comma in auto's (cars) and 's avonds (in the evening). Dutch uses it in a small, fixed set of situations, not as freely as English does.

Use an apostrophe in four cases: before a plural -s or a diminutive -tje that follows a long single vowel, in the frozen 's-forms, in the possessive -s of some names, and where a letter has been left out.

A noun ending in a long single vowel a, o, u, i or y forms its plural by adding -'s. The apostrophe keeps the vowel long: written solid, autos would look like a short o.

• auto → auto's (cars), foto → foto's (photos), menu → menu's (menus).
• baby → baby's (babies), taxi → taxi's (taxis), opa → opa's (grandpas).
• No apostrophe when the vowel is already marked or is a plain -e: café → cafés, garage → garages.

When one of these words ends in -y, the diminutive also keeps the apostrophe before the -tje, because the y cannot be doubled: baby'tje (little baby), pony'tje (little pony). Words ending in -a, -o or -u double the vowel instead and take no apostrophe: opaatje, fotootje, menuutje.

A handful of common time expressions start with 's. The apostrophe replaces the old word des (of the), which Dutch no longer uses on its own.

• 's ochtends / 's morgens (in the morning), 's middags (in the afternoon).
• 's avonds (in the evening), 's nachts (at night).
• 's zomers (in summer), 's winters (in winter).

To show possession, Dutch normally uses van (de auto van Anna), but a name can also take a possessive -s, as explained under possession with van and the genitive. Whether you need an apostrophe depends on the last sound of the name.

• Name ending in a long single vowel → -'s: Anna's boek (Anna's book), Otto's fiets (Otto's bike), Leo's tas (Leo's bag).
• Name ending in a normal consonant → plain -s, no apostrophe: Kevins jas (Kevin's coat), Jans huis (Jan's house).
• Name ending in an s, x or z sound → apostrophe alone, no extra s: Hans' auto (Hans's car), Max' hond (Max's dog).

As in English, an apostrophe marks a letter left out, mainly in casual writing.

• zo'n (from zo een, such a), 'n (een, a), 't (het, it/the).
• m'n (mijn, my), z'n (zijn, his).
• Years: de zomer van '68.

The common error is putting an apostrophe before every plural -s, on the English model. Dutch adds -'s only after a long single vowel a/o/u/i/y. Words ending in -el, -em, -en, -er or -je take a plain -s with no apostrophe: tafels (tables, not tafel's), meisjes (girls), bakkers (bakers). Reserve the apostrophe for cases like auto's, where it protects a long vowel.