I tried lot but not able to do it.

Here is a Program, which can perform upto 99,999 ...
Note: in a vb.net form you have to place one text box named
as  txt1 and one label named as Lab1....
Private Sub txt1_TextChanged(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles txt1.TextChanged
        Try
            If Val(txt1.Text) <> 0 Then
                fun(txt1.Text)
            Else
                Lab1.Text = ""
            End If
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub
    Public Function fun(ByVal t As Integer)
        Dim l As Int16
        l = Len(CStr(t))
        Select Case l
            Case 1
                Lab1.Text = Ones(t)
            Case 2
                Lab1.Text = Case2(t)
            Case 3
                Lab1.Text = Case3(t)
            Case 4
                Lab1.Text = Case4(t)
            Case 5
                Lab1.Text = Case5(t)
        End Select
        fun = Lab1.Text
    End Function
    Public Function Case5(ByVal t As Integer) As String
        Dim L2 As String
        Dim R3 As String
        L2 = Strings.Left(CStr(t), 2)
        R3 = Strings.Right(CStr(t), 3)
        If CInt(R3) = 0 Then
            Case5 = Case2(CInt(L2)) & " Thousand "
        Else
            Case5 = Case2(CInt(L2)) & " Thousand "
            If Strings.Left(R3, 1) = "0" Then
                Case5 = Case5 & " and " & Case2(CInt(R3))
            Else
                Case5 = Case5 & Case3(CInt(R3))
            End If
        End If
    End Function
    Public Function Case2(ByVal t As Integer) As String
        Dim q, r As Int16
        If t > 10 And t < 20 Then
            Case2 = Teens(t)
        Else
            q = Int(t / 10)
            r = t Mod 10
            Case2 = Tens(q) & " " & Ones(r)
        End If
    End Function
    Public Function Case3(ByVal t As Integer) As String
        Dim q1, q2, q, r As Integer
        Dim LabTxt As String
        q1 = Int(t / 100)
        If (t - (q1 * 100)) = 0 Then
            LabTxt = Ones(q1) & " Hundred "
        Else
            LabTxt = Ones(q1) & " Hundred and "
        End If
        q2 = t - (q1 * 100)
        If q2 > 10 And q2 < 20 Then
            Case3 = LabTxt & Teens(q2)
        Else
            q = Int(q2 / 10)
            r = q2 Mod 10
            Case3 = LabTxt & Tens(q) & " " & Ones(r)
        End If
    End Function

    Public Function Case4(ByVal t As Integer) As String
        Dim q As Int16
        Dim r As Int16
        Dim q1 As Int16
        Dim q2 As Int16
        Dim LabTxt As String
        Dim q4 As Integer
        q4 = Int(t / 1000)
        LabTxt = Ones(q4) & " Thousand "
        t = t - q4 * 1000
        If t = 0 Then
            Case4 = LabTxt
            Exit Function
        End If
        q1 = Int(t / 100)
        If q1 = 0 Then
            LabTxt = LabTxt & " and "
            If t > 10 And t < 20 Then
                Case4 = LabTxt & Teens(t)
            Else
                q = Int(t / 10)
                r = t Mod 10
                Case4 = LabTxt & Tens(q) & " " & Ones(r)
            End If
            Exit Function
        End If
        If (t - (q1 * 100)) = 0 Then
            LabTxt = LabTxt & Ones(q1) & " Hundred "
        Else
            LabTxt = LabTxt & Ones(q1) & " Hundred and "
        End If
        q2 = t - (q1 * 100)
        If q2 > 10 And q2 < 20 Then
            Case4 = LabTxt & Teens(q2)
        Else
            q = Int(q2 / 10)
            r = q2 Mod 10
            Case4 = LabTxt & Tens(q) & " " & Ones(r)
        End If
    End Function
    Public Function Ones(ByVal t As Integer) As String
        Ones = ""
        Select Case t
            Case 1
                Return "One"
            Case 2
                Return "Two"
            Case 3
                Return "Three"
            Case 4
                Return "Four"
            Case 5
                Return "Five"
            Case 6
                Return "Six"
            Case 7
                Return "Seven"
            Case 8
                Return "Eight"
            Case 9
                Return "Nine"
        End Select
    End Function
    Public Function Tens(ByVal Que As Int16) As String
        Select Case Que
            Case 1
                Return "Ten"
            Case 2
                Return "Twenty"
            Case 3
                Return "Thirty"
            Case 4
                Return "Forty"
            Case 5
                Return "Fifty"
            Case 6
                Return "Sixty"
            Case 7
                Return "Seventy"
            Case 8
                Return "Eighty"
            Case 9
                Return "Ninty"
        End Select
    End Function

    Public Function Teens(ByVal Que As Int16) As String
        Select Case Que
            Case 11
                Return "Eleven"
            Case 12
                Return "Twelve"
            Case 13
                Return "Thirteen"
            Case 14
                Return "Forteen"
            Case 15
                Return "Fifteen"
            Case 16
                Return "Sixteen"
            Case 17
                Return "Seventeen"
            Case 18
                Return "Eighteen"
            Case 19
                Return "Ninteen"
        End Select
    End Function

Private Sub Button1_Click(ByVal sender As System.Object, 
ByVal e As System.EventArgs) Handles Button1.Click
        Me.TextBox3.Text = CInt(Me.TextBox1.Text) + CInt
(Me.TextBox2.Text)
    End Sub

Answer 3 is wrong