Piav txog lub ntiaj teb hom lus, linguists, zaum siv ntau cov ntsiab cai ntawm cais. Lus yog chav rau hauv pab pawg los ntawm thaj (hwv) hauv paus ntsiab lus, nyob rau hauv lub cheeb tsam ntawm lub grammatical qauv, nyob rau lub hauv paus ntawm cov lus tseeb, cov kev siv nyob rau hauv nyob txhua hnub hais lus.
Siv tus tom kawg kauj, kev soj ntsuam muab faib tag nrho cov lus ntawm lub ntiaj teb no mus rau hauv ob qho loj pawg - nyob thiab tuag lus. Cov yam ntxwv tseem ceeb ntawm cov thawj - siv rau lawv nyob rau hauv txhua hnub kev sib tham, lus xyaum, ib tug kuj zej zog loj ntawm cov neeg (teb chaws). Nyob cov lus yog lossi siv nyob rau hauv txhua hnub kev sib txuas lus, kev hloov, nyuab los yog yooj yim zog thaum lub sij hawm.
Qhov tseem hnov hloov tshwm sim nyob rau hauv lub lexicon (cov lo lus) cov lus: ib feem ntawm lub lo lus obsolete, acquires ib tug archaic xim, thiab sib piv, mus xaiv lub ntsiab tshiab tshwm sim ntau thiab ntau lo lus tshiab (neologisms). Lwm yam lus system (morphological, phonetic, syntactic) muaj ntau inert, hloov heev maj mam thiab coj.
Tuag lus, raws li txwv mus nyob, yog tsis siv nyob rau hauv txhua hnub lus xyaum. Txhua yam tshuab nws unchanged, fwm, yeej tsis hloov li hais. Tuag lus, embodied nyob rau hauv ib tug ntau yam ntawm daim ntawv cov ntaub ntawv.
Tag nrho cov neeg tuag cov lus yuav tsum tau muab faib mus rau hauv ob lub ntsiab pawg: thawj, cov neeg uas tej tsam nyob rau hauv lub deb yav dhau los, tau siv nyob sib txuas lus thiab ces, rau ntau yam yog vim li cas, muaj ceased yuav tsum tau siv nyob rau hauv ib tug nyob tib neeg kev sib txuas lus (Latin, Greek, Coptic, Laus Norse, Gothic). Qhov thib ob pab pawg neeg uas twb tuag lawm lus muaj xws li cov neeg nyob rau hauv uas tsis muaj ib tug puas tau hais; Lawv tsim los ua ib zog (li, piv txwv li, muaj ib lub qub Slavonic lus - cov lus ntawm lub Christian liturgical phau ntawv). Tuag lus feem ntau hloov mus rau hauv ib tug nyob, nquag siv (piv txwv li, Greek tau muab txoj kev uas niaj hnub lus thiab dialects ntawm tim Nkij teb chaws).
Latin occupies ib tug tshwj xeeb qhov chaw ntawm cov so. Yog tsis muaj ib tug tsis ntseeg, Latin - ib tug tuag lawm cov lus: nyob rau hauv ib tug cus ciav conversational xyaum nws tsis txhob noj ib ncig ntawm lub thib rau lub xyoo pua AD. Tab sis, nyob rau hauv lwm cov tes, Latin pom lub widest daim ntawv thov nyob rau hauv lub chaw ua tshuaj, kev kho mob, kev terminology, Catholic pe hawm (Latin - lub official "xeev" lus ntawm tus Vaj Ntsuj Saib thiab Vatican City State). Raws li koj tau pom, "tuag" Latin yog dav siv nyob rau hauv ntau yam teb ntawm lub neej science, kev txawj ntse. Tag nrho cov loj philological universities tas muaj xws li Latin nyob rau hauv cov ntaub ntawv kawm, kom yog li kev lig kev cai ntawm classical mas kev kawm ntawv. Nyob rau hauv tas li ntawd, cov neeg tuag cov lus - ib qhov chaw ntawm nyuag thiab intensive aphorisms uas tau dhau los ntawm lub hnub nyoog: yog hais tias koj xav tau kev thaj yeeb - npaj rau tsov rog; Memento Mori; Tus kws kho mob, kho koj tus kheej - tag nrho cov sayings "yug" los ntawm lub Latin. Latin - ib tug heev muaj kuab thiab zoo-ua lus, cam khwb cia, no-nonsense thiab hais lus husk; nws tsis yog tsuas yog siv rau utilitarian lub hom phiaj (sau ntawv yuav tshuaj, tus tsim ntawm ib tug scientific Thesaurus), tab sis yog nyob rau hauv ib txoj kev ib tug qauv, standard lus.