Dutch slang and informal language — understanding how Dutch people actually talk in casual settings. Standard Dutch taught in courses is somewhat formal; real Dutch conversation is full of contractions, slang, and informal expressions that are not in textbooks. Key informal contractions: da’s (= dat is), wa’s (= wat is), je (= jij in informal contexts), m’n (= mijn), z’n (= zijn/her), d’r (= haar/er). In speech, these contractions are ubiquitous.
Amsterdam slang with broad reach: vet (cool/great — literally fat), tof (cool/nice), lekker (nice/great — extremely versatile: lekker slapen = sleep well, lekker weer = nice weather, lekker bezig = sarcastically “nice job”), mafkees (nutcase/weirdo), gast (guy/bloke), kapsones (arrogance, thinking too highly of yourself), ouwehoeren (to chat/ramble on). Surinamese-influenced slang common in Dutch cities: makker (friend/mate), brada (brother).
Flemish/Belgian informal Dutch adds a layer: proper (nice/clean), plezant (fun/pleasant), allez (come on!/right then!), zeker (certainly/sure — used much more frequently than in the Netherlands), ambetant (annoying). Understanding regional variation in informal Dutch takes time but shows genuine cultural investment that native speakers notice and appreciate.