Present participle; Past participle - building - built Present - build - build - builds - build - build - build Past - built - built - built - built - built - built Future - will build - will build - will build - will build - will build - will build Present conditional - would build - would build - would build - would build - would build - would build Present Perfect - have built - have built - has built - have built - have built - have built Past Perfect - had built - had built - had built - had built - had built - had built Future Perfect - will have built - will have built - will have built - will have built - will have built - will have built Past conditional - would have built - would have built - would have built - would have built - would have built - would have built Imperative - - - build - - - - - - - -