Present participle; Past participle - leavening - leavened Present - leaven - leaven - leavens - leaven - leaven - leaven Past - leavened - leavened - leavened - leavened - leavened - leavened Future - will leaven - will leaven - will leaven - will leaven - will leaven - will leaven Present conditional - would leaven - would leaven - would leaven - would leaven - would leaven - would leaven Present Perfect - have leavened - have leavened - has leavened - have leavened - have leavened - have leavened Past Perfect - had leavened - had leavened - had leavened - had leavened - had leavened - had leavened Future Perfect - will have leavened - will have leavened - will have leavened - will have leavened - will have leavened - will have leavened Past conditional - would have leavened - would have leavened - would have leavened - would have leavened - would have leavened - would have leavened Imperative - - - leaven - - - - - - - -