Da or de: a glass of water

The da rule

A quantity links to the stuff it measures with da, and the stuff stays bare. The left side can be an adverb, kiom, or a measure noun:

• glaso da akvoa glass of water
• taso da teoa cup of tea
• botelo da laktoa bottle of milk

The noun after da never takes -n, even when the whole phrase is the object. The -n goes on the measure word:

• Mi trinkis glason da akvo. - I drank a glass of water.

123

1. 1kruĉo da akvo
2. 2botelo da suko
3. 3bovlo da fruktoj

Kruĉo da akvo, a jug of water; botelo da suko, a bottle of juice; bovlo da fruktoj, a bowl of fruit. Each container measures what is in it.

Never da before la

Da measures stuff in general. Once the stuff is a particular, identified thing (after la, tiu or a possessive), standard usage switches to de. A few writers defend da here when a real measure is meant, but de is what you will read and what to write:

The check is mechanical: if the next word is la, tiu or a possessive, write de.

• Ŝi trinkis glason de la vino. - She drank a glass of the wine.

da vs de: the minimal pairs

Even with no la, the two words say different things:

Da answers how much; de answers what kind or whose. The clearest word for the empty wine glass is the compound vinglaso; you will still meet glaso de vino used loosely for a glassful, but the careful form is glaso da vino. When in doubt, de is the general word and da the specialist.