Present participle; Past participle - proofing - proofed Present - proof - proof - proofs - proof - proof - proof Past - proofed - proofed - proofed - proofed - proofed - proofed Future - will proof - will proof - will proof - will proof - will proof - will proof Present conditional - would proof - would proof - would proof - would proof - would proof - would proof Present Perfect - have proofed - have proofed - has proofed - have proofed - have proofed - have proofed Past Perfect - had proofed - had proofed - had proofed - had proofed - had proofed - had proofed Future Perfect - will have proofed - will have proofed - will have proofed - will have proofed - will have proofed - will have proofed Past conditional - would have proofed - would have proofed - would have proofed - would have proofed - would have proofed - would have proofed Imperative - - - proof - - - - - - - -