Present participle; Past participle - curtaining - curtained Present - curtain - curtain - curtains - curtain - curtain - curtain Past - curtained - curtained - curtained - curtained - curtained - curtained Future - will curtain - will curtain - will curtain - will curtain - will curtain - will curtain Present conditional - would curtain - would curtain - would curtain - would curtain - would curtain - would curtain Present Perfect - have curtained - have curtained - has curtained - have curtained - have curtained - have curtained Past Perfect - had curtained - had curtained - had curtained - had curtained - had curtained - had curtained Future Perfect - will have curtained - will have curtained - will have curtained - will have curtained - will have curtained - will have curtained Past conditional - would have curtained - would have curtained - would have curtained - would have curtained - would have curtained - would have curtained Imperative - - - curtain - - - - - - - -