Proto-Slavic *čьto

→ Belarusian што (inherited)

→ Bulgarian що (inherited)

→ Czech co (inherited)

→ Old Church Slavonic чьто (inherited)

→ Lower Sorbian co (inherited)

→ Lithuanian keisti (cognate)

→ Macedonian што (inherited)

→ Polish co (inherited)

→ Polabian cü (inherited)

→ Russian что (inherited)

→ Rusyn што (inherited)

→ Serbo-Croatian šta (inherited)

→ Serbo-Croatian što (inherited)

→ Serbo-Croatian шта (inherited)

→ Serbo-Croatian што (inherited)

→ Serbo-Croatian ča (derived)

→ Slovak čo (inherited)

→ Silesian co (inherited)

→ Ukrainian що (inherited)

→ Old Polish czso (mention)