In the article the conformities to law of formation of imperative mood verbs on -ити are investigated. The verb of this class elect an accentual paradigm after three accentual rears, for example: a) бfвити – бfвлю, бfвиш, бfвлять; imp. бfв, бfвмо, бfвте; b) щербbти – щерблo, щербbш, щерблzть; imp. щербb, щербsм(о), щербsть; c) робbти – роблo, рjбиш, рjблять; imp. робb, робsм(о), робsть. Obviously, that imperative word-parts of verbs eventual and movable accentual types are identical as from the point of their marking, so from the point of view of morphological registration; they, thus, together matched against the word-parts of root-accented verbs. That is why, the special attention in the article is devoted to the phenomena of type тумfнbти – тумfнo, тумfнbш, тумfнzть; imp. тумfнь and туманb, when a verb has two parallel accentual paradigms: clearly, that it is on the eve of accentual changes. About their direction testify, for example, such cases, when former звузbти – звужe, звузbш; imp. звузb, звузsть is deputized in a modern language звeзити – звeжу, звeзиш; imp. звeзь, звeзьте etc. The actual problem for modern Ukrainian linguistics is to find out the measure of accordance to the Ukrainian system of imperative mood word-parts of type крtсли or крtсль (from крtслити) etc., погsрш or погsрши (from погsршити) etc., засвsдчи or засвsдч (from засвsдчити), and also of type запtвни (from запtвнити) etc