Private Function NumbersToWords(ByVal num As Currency) As String
Dim power_value(1 To 5) As Currency
Dim power_name(1 To 5) As String
Dim digits As Integer
Dim result As String
Dim i As Integer

' Initialize the power names and values.
power_name(1) = "trillion": power_value(1) = 1000000000000#
power_name(2) = "billion": power_value(2) = 1000000000
power_name(3) = "million": power_value(3) = 1000000
power_name(4) = "thousand": power_value(4) = 1000
power_name(5) = "": power_value(5) = 1
For i = 1 To 5
    ' See if we have digits in this range.
    If num >= power_value(i) Then
        ' Get the digits.
        digits = Int(num / power_value(i))
        ' Add the digits to the result.
        If Len(result) > 0 Then result = result & ", "
        result = result & Words_1_999(digits) & " " & power_name(i)
        ' Get the number without these digits.
        num = num - digits * power_value(i)
    End If
Next i
NumbersToWords = Trim$(result)
End Function

' Return words for this value between 1 and 999.
Private Function Words_1_999(ByVal num As Integer) As String
Dim hundreds As Integer
Dim remainder As Integer
Dim result As String
    hundreds = num \ 100
    remainder = num - hundreds * 100
    If hundreds > 0 Then
        result = Words_1_19(hundreds) & " hundred "
    End If
    If remainder > 0 Then
        result = result & Words_1_99(remainder)
    End If
    Words_1_999 = Trim$(result)
End Function

' Return a word for this value between 1 and 19.
Private Function Words_1_19(ByVal num As Integer) As String
Select Case num
    Case 1
        Words_1_19 = "one"
    Case 2
        Words_1_19 = "two"
    Case 3
        Words_1_19 = "three"
    Case 4
        Words_1_19 = "four"
    Case 5
        Words_1_19 = "five"
    Case 6
        Words_1_19 = "six"
    Case 7
        Words_1_19 = "seven"
    Case 8
        Words_1_19 = "eight"
    Case 9
        Words_1_19 = "nine"
    Case 10
        Words_1_19 = "ten"
    Case 11
        Words_1_19 = "eleven"
    Case 12
        Words_1_19 = "twelve"
    Case 13
        Words_1_19 = "thirteen"
    Case 14
        Words_1_19 = "fourteen"
    Case 15
        Words_1_19 = "fifteen"
    Case 16
        Words_1_19 = "sixteen"
    Case 17
        Words_1_19 = "seventeen"
    Case 18
        Words_1_19 = "eightteen"
    Case 19
        Words_1_19 = "nineteen"
End Select
End Function

' Return a word for this value between 1 and 99.
Private Function Words_1_99(ByVal num As Integer) As String
Dim result As String
Dim tens As Integer
tens = num \ 10
If tens <= 1 Then ' 1 <= num <= 19
    result = result & " " & Words_1_19(num)
Else
' 20 <= num
' Get the tens digit word.
    Select Case tens
        Case 2
            result = "twenty"
        Case 3
            result = "thirty"
        Case 4
            result = "forty"
        Case 5
            result = "fifty"
        Case 6
            result = "sixty"
        Case 7
            result = "seventy"
        Case 8
            result = "eighty"
        Case 9
            result = "ninety"
    End Select
' Add the ones digit number.
    result = result & " " & Words_1_19(num - tens * 10)
End If
Words_1_99 = Trim$(result) End Function