Principal Parts of Latin Verbs and Tense/Voice Formation
 
| System
  of Tenses | Principal Parts
  Used for Tense Formation | |
| Active Voice | Passive Voice | |
| Present(present,
  imperfect, future) | 1st/2nd
  principal parts | 1st/2nd
  principal parts | 
| Perfect (perfect,
  pluperfect, future perfect) | 3rd principal
  part | 4th principal
  part + form of esse |