Verbs based on root *let-
lětati
3sg.prs lětaetъ (aje-stem), 2/3sg.aor lěta (a-stem)
Leskien class III
ipf aspect
intransitive
motion verb
prefix variation: vъ-, vъz-, iz-, ob-, otъ-, po-, pri-, prě- (ipf)
SJS
letěti
3sg.prs letitъ (i-stem), 2/3sg.aor letě (ě-stem)
Leskien class IV
ipf aspect
intransitive
motion verb
prefix variation: vъ-, vъz-, iz-, niz-, ob-, otъ-, po-, pri-, prě-, prěvъz-, sъ-, u- (pf)
given lit. lėkti as a possible cognate, ESSJ (410) mentions explanations based on 1. influence of another root (e.g. *pet- of pъtica ʹbirdʹ, by Bezlaj), 2. a present te-stem (*lek-te-, see plet-), 3. a denominal verb based on *lek-to- (Meillet, also preferred by Derksen 271, wiktionary, and plausible from the perspective of a stative/fientive meaning), 4. a derivate from a-/aje-verb lětati, built with a tā-suffix (Machek)
LIV (411) mentions only lėkti
Examples in the corpus: izletja lětati letja otletja poletěti
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