er meaning 'of them': Ik heb er drie

When you count something but leave out the noun, Dutch fills the gap with er. English drops the noun and says I have three; Dutch cannot, so it adds er to mean of them: Hoeveel appels heb je? — Ik heb er drie. (How many apples do you have? — I have three.) This is the quantitative er, and English has no single word for it.

Whenever you replace a counted noun with a bare number or amount, put er in front of the quantity word. The pattern is er + (number or quantity word), with the noun gone.

1. Drop the noun you are counting: Ik heb drie appels → Ik heb ... drie.
2. Put er in where the noun was, before the quantity: Ik heb er drie.
3. This works with any number or amount word: Ik heb er twee (two), er veel (many), er weinig (few), er genoeg (enough), er geen (none).

Historically this er is a shortened ervan (of it / of them), so in a longer sentence you may still hear the full van kept before the verb: Ik heb er drie van gegeten (I ate three of them). In everyday Dutch the van is usually dropped and er alone carries the meaning.

The quantitative er always needs a number or amount to lean on. A quantity word must follow: Ik heb er veel is right, but a bare Ik heb er is not a complete answer — you drop the er entirely (Ik heb ze) or you keep the quantity.

The word er comes early in the middle of the sentence, right after the verb (and the subject in an inverted sentence). The number or amount stays further along, near the end.

• Simple: Ik heb er gisteren drie gekocht. (I bought three of them yesterday.)
• In a question the subject slips between them: Heb je er nog twee? (Do you still have two of them?)
• In counting sentences you can meet er twice — once to say something exists, once for the quantity: Er zijn er nog maar twee. (There are only two left.)

English speakers leave the er out, because I have three needs no extra word: they write Ik heb drie, which sounds unfinished to Dutch ears. Once the noun is gone, the er is not optional — say Ik heb er drie. Do not confuse this counting er with the er that combines with a preposition (Ik denk eraan, I'm thinking about it — see erop, ermee, eraan); the quantitative one always sits next to a number or amount.