Sub ListChange()
Application.ScreenUpdating = False
Dim MyList() As String, i As Long
Options.DefaultHighlightColorIndex = wdYellow
MyList = Split("additionally,ah,almost,big,can be,could,could be,generally speaking,he,in,it,it is,low,many,may,might,most,plenty,she,should,some, these,they,this is,we,with", ",")
With ActiveDocument.Range.Find
  .ClearFormatting
  .Replacement.ClearFormatting
  .Replacement.Highlight = True
  .Replacement.Text = "^&"
  .MatchWholeWord = True
  For i = 0 To UBound(MyList())
    .Text = MyList(i)
    .Execute Replace:=wdReplaceAll
  Next
End With
Application.ScreenUpdating = True
End Sub