Present participle; Past participle - shortening - shortened Present - shorten - shorten - shortens - shorten - shorten - shorten Past - shortened - shortened - shortened - shortened - shortened - shortened Future - will shorten - will shorten - will shorten - will shorten - will shorten - will shorten Present conditional - would shorten - would shorten - would shorten - would shorten - would shorten - would shorten Present Perfect - have shortened - have shortened - has shortened - have shortened - have shortened - have shortened Past Perfect - had shortened - had shortened - had shortened - had shortened - had shortened - had shortened Future Perfect - will have shortened - will have shortened - will have shortened - will have shortened - will have shortened - will have shortened Past conditional - would have shortened - would have shortened - would have shortened - would have shortened - would have shortened - would have shortened Imperative - - - shorten - - - - - - - -