question: public static void expandNumber ( String numberString , WordRelation wordRelation , Item tokenItem ) { int numDigits = numberString . length ( ) ; if ( numDigits == 0 ) { } else if ( numDigits == 1 ) { expandDigits ( numberString , wordRelation , tokenItem ) ; } else if ( numDigits == 2 ) { expand2DigitNumber ( numberString , wordRelation , tokenItem ) ; } else if ( numDigits == 3 ) { expand3DigitNumber ( numberString , wordRelation , tokenItem ) ; } else if ( numDigits < 7 ) { expandBelow7DigitNumber ( numberString , wordRelation , tokenItem ) ; } else if ( numDigits < 10 ) { expandBelow10DigitNumber ( numberString , wordRelation , tokenItem ) ; } else if ( numDigits < 13 ) { expandBelow13DigitNumber ( numberString , wordRelation , tokenItem ) ; } else { expandDigits ( numberString , wordRelation , tokenItem ) ; } }
target:  Expands a digit string into a list of English words of those digits. For example, "1234" expands to "one two three four"