If r >= 30 Then
                    Shape1.BackStyle = 1
                    Shape1.BackColor = QBColor(12)
                    label1.ForeColor = vbRed
                     Timer2.Enabled = False
                    Label3.Caption = Now()
                    h(1) = Hour(Now)
                    m(1) = Minute(Now)
                    s(1) = Second(Now)
                Else
                    Shape1.BackStyle = 1
                    Shape1.BackColor = QBColor(10)
                    label1.ForeColor = vbGreen
                    Timer2.Enabled = True
                    Timer2.interval = 10000
                    Label2.Caption = Now()
                    h(0) = Hour(Now)
                    m(0) = Minute(Now)
                    s(0) = Second(Now)
            End If
        Label4.Caption = h(0) - h(1) & " : " & m(0) - m(1) & " : " & s(0) - s(1)
End Sub

说明：在label2显示一个时间，在label3显示一个时间，现在想在label4上显示两个时间的时间差，但运行后label4显示的是与label2同步运行的时间，哪里错了呢？

那想在label4上显示两个时间的时间差，应该怎么改呢？