question: public static void expandID ( String numberString , WordRelation wordRelation , Item tokenItem ) { int numberDigits = numberString . length ( ) ; if ( ( numberDigits == 4 ) && ( numberString . charAt ( 2 ) == '0' ) && ( numberString . charAt ( 3 ) == '0' ) ) { if ( numberString . charAt ( 1 ) == '0' ) { expandNumber ( numberString , wordRelation , tokenItem ) ; } else { expandNumber ( numberString . substring ( 0 , 2 ) , wordRelation , tokenItem ) ; wordRelation . addWord ( tokenItem , "hundred" ) ; } } else if ( ( numberDigits == 2 ) && ( numberString . charAt ( 0 ) == '0' ) ) { wordRelation . addWord ( tokenItem , "oh" ) ; expandDigits ( numberString . substring ( 1 , 2 ) , wordRelation , tokenItem ) ; } else if ( ( numberDigits == 4 && numberString . charAt ( 1 ) == '0' ) || numberDigits < 3 ) { expandNumber ( numberString , wordRelation , tokenItem ) ; } else if ( numberDigits % 2 == 1 ) { String firstDigit = digit2num [ numberString . charAt ( 0 ) - '0' ] ; wordRelation . addWord ( tokenItem , firstDigit ) ; expandID ( numberString . substring ( 1 , numberDigits ) , wordRelation , tokenItem ) ; } else { expandNumber ( numberString . substring ( 0 , 2 ) , wordRelation , tokenItem ) ; expandID ( numberString . substring ( 2 , numberDigits ) , wordRelation , tokenItem ) ; } }
target:  Expands the given number string as pairs as in years or IDs