"I love you."
Translation:Jeg elsker deg.
Du = thou, Deg = thee.
Germanic languages once had 4 cases, in Old English these were: ic/mec/mīn/mē, þū/þec/þīn/þē, wē/ūs/ūre/ūs, gē/ēow/ēower/ēow; in Old Norse (as in Icelandic): ik/mik/mínn/mír, þú/þik/þínn/þír, vér/oss/várr/oss, ér (later þér)/yðr/yðvar/yðr.
These became: English I/me/my/me, thou/thee/thy/thee, we/us/our/us, ye/you/your/you; and Norwegian jeg/meg/min/meg, du/deg/din/deg, vi/oss/vår/oss, dere/dere/deres/dere.
Note how English merges the direct object and indirect object 'mec' and 'mē' (me), 'þec' and 'þē' (thee) into the same as the indirect object. Norwegian does the same but into the same as the direct object (þik > deg, mik > meg).