Present participle; Past participle - costing - cost Present - cost - cost - costs - cost - cost - cost Past - cost - cost - cost - cost - cost - cost Future - will cost - will cost - will cost - will cost - will cost - will cost Present conditional - would cost - would cost - would cost - would cost - would cost - would cost Present Perfect - have cost - have cost - has cost - have cost - have cost - have cost Past Perfect - had cost - had cost - had cost - had cost - had cost - had cost Future Perfect - will have cost - will have cost - will have cost - will have cost - will have cost - will have cost Past conditional - would have cost - would have cost - would have cost - would have cost - would have cost - would have cost Imperative - - - cost - - - - - - - -