Questions & Answers about Er is stof in mijn oog.
Here er is not talking about a place. It is an existential er, used in sentences like Er is ... / Er zijn ..., which correspond to English There is ... / There are ....
So:
- Er is stof in mijn oog. = There is dust in my eye.
In this kind of sentence, er is basically a grammatical placeholder.
Because stof is treated as singular in Dutch.
Even though dust consists of many tiny particles, stof is normally an uncountable mass noun, just like English dust. Mass nouns usually take singular agreement:
If you had a plural countable noun, you would use zijn:
- Er zijn stenen in de tuin. = There are stones in the garden.