Present participle; Past participle - doubling - doubled Present - double - double - doubles - double - double - double Past - doubled - doubled - doubled - doubled - doubled - doubled Future - will double - will double - will double - will double - will double - will double Present conditional - would double - would double - would double - would double - would double - would double Present Perfect - have doubled - have doubled - has doubled - have doubled - have doubled - have doubled Past Perfect - had doubled - had doubled - had doubled - had doubled - had doubled - had doubled Future Perfect - will have doubled - will have doubled - will have doubled - will have doubled - will have doubled - will have doubled Past conditional - would have doubled - would have doubled - would have doubled - would have doubled - would have doubled - would have doubled Imperative - - - double - - - - - - - -