Here's something I put together from the link you posted and another link that you will see commented out in the code.  When you click on the map it will draw a square 10x10 map units from where you clicked. I work in metres so this draws a reasonably sized graphic.

Create an add-in with a tool and add this to the class.

protected override void OnMouseDown(MouseEventArgs arg)
    {

        IMap _map = ArcMap.Document.FocusMap;
        IScreenDisplay3 _display = (IScreenDisplay3)ArcMap.Document.ActiveView.ScreenDisplay;
        ESRI.ArcGIS.Geometry.IPoint _clickedPoint = _display.DisplayTransformation.ToMapPoint(arg.Location.X, arg.Location.Y);

        ESRI.ArcGIS.Display.IRgbColor rgbColor = new ESRI.ArcGIS.Display.RgbColorClass();
        rgbColor.Red = 255;

        ESRI.ArcGIS.Display.IColor color = rgbColor; // Implicit cast.
        ESRI.ArcGIS.Display.ISimpleFillSymbol simpleFillSymbol = new
            ESRI.ArcGIS.Display.SimpleFillSymbolClass();
        simpleFillSymbol.Color = color;

        ESRI.ArcGIS.Display.ISymbol symbol = simpleFillSymbol as
            ESRI.ArcGIS.Display.ISymbol; // Dynamic cast.


        ////http://help.arcgis.com/en/sdk/10.0/arcobjects_net/conceptualhelp/index.html#//0001000002wm000000

        ESRI.ArcGIS.Geometry.IPointCollection4 _poly = (ESRI.ArcGIS.Geometry.IPointCollection4)(new ESRI.ArcGIS.Geometry.Polygon());
        _poly.AddPoint(_clickedPoint, Type.Missing, Type.Missing);

        ESRI.ArcGIS.Geometry.IPoint _pnt = new ESRI.ArcGIS.Geometry.Point();
        _pnt.PutCoords(_clickedPoint.X + 10, _clickedPoint.Y);
        _poly.AddPoint(_pnt, Type.Missing, Type.Missing);
        _pnt.PutCoords(_clickedPoint.X + 10, _clickedPoint.Y + 10);
        _poly.AddPoint(_pnt, Type.Missing, Type.Missing);
        _pnt.PutCoords(_clickedPoint.X, _clickedPoint.Y + 10 );
        _poly.AddPoint(_pnt, Type.Missing, Type.Missing);

        _poly.AddPoint(_clickedPoint, Type.Missing, Type.Missing);            _display.StartDrawing(_display.hDC, (System.Int16)ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache);
        _display.SetSymbol(symbol);
        _display.DrawPolygon(((ESRI.ArcGIS.Geometry.IPolygon)_poly));
        _display.FinishDrawing();



            base.OnMouseDown(arg);
    }


.net arcobjects draw polygon(rectangle) can not start at the preferred location
As someone who is at (near-)native level of English, I know all of these words, but as I'm not immersed in an area where use of English is prevalent, (as of now I am living in the Netherlands,) I don't encounter these words often enough to start seeing obvious patterns between the differences, and the dictionaries I have used didn't help. I have some general ideas, although I have general ideas on the meaning of some of the words.

Propensity seems to be a 'natural' inclination, i.e. "Man has the propensity to be selfish", and disposition seems to be related to opinions as in "He has a disposition to agree with those that are close to him." I don't have the faintest idea about the differences between the other three words that are left though.

Could anyone care to explain this all to me?
