EN/CityGML-Tutorial/chapter-2:-Building/LOD1.md

@@ -80,7 +80,7 @@ SketchUp is a well known and commonly used 3D Computer Aided Design (CAD) modeli
 
 In order to make a conversion from Sketchup to CityGML using FME, the modeling process in Sketchup needs to meet some requirements. The naming of the layers within CityGML has to follow a specific schema. For LOD1 all the building geometries must be under one layer other than Layer0. For example purpose, the building show in the below figure is kept under layer "bldg". 
 
->It is recommended to create a new layer in SketchUp in addition to default "Layer0" because SketchUp draws edges together with polygons. Because CityGML needs polygons to model buildings, all the polygon corresponding to its appropriate BoundarySurface can be classified in different layers. Layer0 cane be used to store edges and other artifcats of the 3D model. Make sure that all the required layers except Layer0 are visible before saving and closing SketchUp. This will guarantee that all the SketchUp layers are imported inside FME and Layer0 is automatically filtered out as it is not visible. If Layer0 is kept visible in the SketchUp file it can also be later filtered out using FME transformer [AttributeFilter](https://www.safe.com/transformers/attribute-filter/) so that it plays no part in the conversion process to CityGML.
+>It is recommended to create a new layer in SketchUp in addition to default "Layer0" because SketchUp draws edges together with polygons. Because CityGML needs polygons to model buildings, all the polygon corresponding to its appropriate semantic elements can be classified in different layers. Layer0 can be used to store edges and other artifacts of the 3D model. Make sure that all the required layers except Layer0 are visible before saving and closing SketchUp. This will guarantee that all the SketchUp layers are imported inside FME and Layer0 is automatically filtered out as it is not visible. If Layer0 is kept visible in the SketchUp file it can also be later filtered out using FME transformer [AttributeFilter](https://www.safe.com/transformers/attribute-filter/) so that it plays no part in the conversion process to CityGML.
 
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