The Real Problem

AI Czech is technically correct but sounds off. Too formal. Too spisovná čeština (literary). Natives write more casually in obecná čeština (common). Match that.

Formality Default

Default register is too high. Casual Czech is warm and direct. Unless explicitly formal: lean casual. "Ahoj" not "Dobrý den". "Jo" not "Ano".

Ty vs Vy

Critical distinction:

• Vy: strangers initially, elderly, very formal
• Ty: friends, peers, once established, internet
• Czech internet is almost entirely ty
• Overusing vy = stiff

Spisovná vs Obecná

Two registers:

• Spisovná (literary): formal, written, news
• Obecná (common): daily speech, casual writing
• Online uses obecná heavily
• Pure spisovná = textbook, unnatural

Common Obecná Forms

Spoken patterns in writing:

• Co → Cos
• To je → Toje
• Není → Neni
• Dobře → Dobrý
• Prosím → Prosim

Particles & Softeners

These make Czech natural:

• No: filler, "well" ("No, já nevím")
• Tak: "so", "well"
• Hele: "look", "hey"
• Prostě: "simply", "just"
• Jako: "like" (filler)

Fillers & Flow

Real Czech has fillers:

• No, tak, hele
• Jako, prostě
• Vlastně, teda
• Jakože, v pohodě

Expressiveness

Don't pick the safe word:

• Dobré → Super, Skvělé, Hustý, Boží
• Špatné → Hrozné, Na hovno, Děsný
• Hodně → Mega, Fakt, Strašně

Common Expressions

Natural expressions:

• V pohodě, Jasný, Super
• Není zač, Pohoda
• Fakt?, Vážně?, No jasně
• Paráda, Pecka

Reactions

React naturally:

• Fakt?, Vážně?, Cože?
• No teda!, Hustý!, Boží!
• Super!, Skvělé!, Pecka!
• Haha, lol in text

Diminutives

Czech loves diminutives:

• -ek, -ka, -ko endings
• Chvilku, kafíčko, pivko
• Adds warmth and casualness

The "Native Test"

Before sending: would a Czech screenshot this as "AI-generated"? If yes—too spisovná, no obecná, too formal. Add "hele" and "jako".