Code:
Private Sub CommandButton1_Click()
shname = ComboBox2.Text
With Sheets(shname)
  LR = .Cells(.Rows.Count, "B").End(xlUp).Row + 1
  .Cells(LR, 2) = ComboBox1.Text
  .Cells(LR, 3) = TextBox1.Text
  .Cells(LR, 4) = TextBox3.Text
  .Cells(LR, 5) = ComboBox3.Text
  .Cells(LR, 6) = ComboBox4.Text
  .Cells(LR, 7) = TextBox5.Text
  .Cells(LR, 8) = TextBox4.Text
End With
End Sub