Could you please help me understand the etymology of words used to start questions? I am particularly interested by the words 'how' and 'why'. Thank you!
The OED gives them both as coming from Old English:
how Old English hú < *hwó, corresponding to Old Frisian hû, hô, Old Saxon hwô, hwuo, wô (Middle Dutch hoe (ho, hou), Dutch hoe, Middle Low German woe), Old High German (Tatian) wuo < Germanic *hwô, an adverbial formation from the interrogative pronoun stem hwa- who? Parallel to Middle Dutch hú, and to Gothic hwaiwa, Old High German hweo, weo, wio, German wie, with different suffixes.
why Old English hwí , hwý instrumental case of hwæt what pron., adj.1, adv., int., conj., and n., governed by to or for (see forwhy adv. and conj.) or used simply as adverb, corresponding to Old Saxon hwî used with prepositions (bi hwî , te hwî ) and simply = why, wherefore, Old Norse hví used as dative of hvat , and as adverb = why (Middle Swedish, Danish hvi ) < Old Germanic *χwī < Indo-European *qwei , locative < *qwo- who pron.; compare Greek (Doric) πεῖ where.