Present participle; Past participle - crackling - crackled Present - crackle - crackle - crackles - crackle - crackle - crackle Past - crackled - crackled - crackled - crackled - crackled - crackled Future - will crackle - will crackle - will crackle - will crackle - will crackle - will crackle Present conditional - would crackle - would crackle - would crackle - would crackle - would crackle - would crackle Present Perfect - have crackled - have crackled - has crackled - have crackled - have crackled - have crackled Past Perfect - had crackled - had crackled - had crackled - had crackled - had crackled - had crackled Future Perfect - will have crackled - will have crackled - will have crackled - will have crackled - will have crackled - will have crackled Past conditional - would have crackled - would have crackled - would have crackled - would have crackled - would have crackled - would have crackled Imperative - - - crackle - - - - - - - -