Compound verbs
Verbs made of more than one stem, whose stems cannot be separated by other suffixes and which answer one question are compound verbs: sayr etmoq, taq etmoq, olib kelmoq, bunyod qilmoq. They are made by adding qil-, et-, bo‘l- to nouns, adjectives, numerals, pronouns, adverbs, interjections and imitative words, and by adding verbs like kelmoq, ketmoq to verb forms: tarbiya qilmoq (to bring up), eski bo‘lmoq (to become old), bir bo‘lmoq (to unite), kim bo‘lmoq (to become somebody), dod solmoq (to cry out), chirs etmoq (to make a crack sound). Both parts of a compound verb keep their lexical meaning: borib keldi — went and came. The parts are written separately. If the second part loses its meaning, it is not a compound verb but an auxiliary construction: o‘qib chiqdi.
“Compound verb builders”: children add qil-, et-, bo‘l- to nouns to make compound verbs (tarbiya + qil, sayr + et).