Old Norse skulu

← Old English sculan (cognate)

← English shall (cognate)

← Proto-Germanic *skulaną (inherited)

← Proto-Indo-European *skel- (root)

← Proto-Indo-European *skel- (derived)

→ Old English sculan (cognate)

→ Danish skulle (derived)

→ Faroese skula (derived)

→ Old Swedish skula (inherited)

→ Icelandic skulu (inherited)

→ Norwegian Bokmål skulle (derived)

→ Norwegian Nynorsk skulle (inherited)

→ Norwegian Nynorsk sku (inherited)

→ Norwegian Nynorsk skulla (derived)

→ Old Norse vilja (mention)

→ Old Norse skaltu (mention)

→ Old Saxon skulan (cognate)

→ Swedish ska (mention)

→ Swedish skola (inherited)