[*] 182. Four verbs, dīcō , dūcō , faciō , ferō ,—with their compounds, drop the vowel-termination of the Imperative, making dīc , dūc, făc , fĕr; but compounds in -ficiō retain it, as, cōnfice .
[*] Note.--The imperative forms dīce, dūce, face (never fere ), occur in early Latin.
[*] a. For the imperative of sciō , the future form scītō is always used in the singular, and scītōte usually in the plural.