A sentence is negated by adding the prefix ne- to the verb.
Es nerunāju latviski.
I do not speak Latvian.
⚠️ Latvian uses double (multiple) negation: negative pronouns and adverbs require the verb to be negated as well.
Es nekad neēdu gaļu.
I never eat meat.
Neviens nezina.
No one knows.
After a negated verb, the direct object often takes the genitive case instead of the accusative.
The verb būt (to be) has a special negative, nav, meaning ‘is not / are not / there is no’. What ‘is not there’ goes in the genitive.
Man nav naudas.
I have no money.
Šeit nav neviena.
There is no one here.
‘Neither … nor’ is expressed with ne … ne, and the verb is still negated.
Es nedzeru ne kafiju, ne tēju.
I drink neither coffee nor tea.