Private Sub CommandButton1_Click()
la_val1 = IIf(ComboBox1.Value <> "", ComboBox1.Value, "")
la_val2 = IIf(ComboBox2.Value <> "", IIf(ComboBox1.Value <> "", Chr(10), "") & ComboBox2.Value, "")
la_val3 = IIf(ComboBox3.Value <> "", IIf(ComboBox1.Value <> "" Or ComboBox2.Value <> "", Chr(10), "") & ComboBox3.Value, "")
[A1].Value = la_val1 & la_val2 & la_val3
End Sub