diff --git a/.DS_Store b/.DS_Store
index c4eb021..001d2ab 100644
Binary files a/.DS_Store and b/.DS_Store differ
diff --git a/.gitignore b/.gitignore
index 68bc17f..e05e2e7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -158,3 +158,4 @@ cython_debug/
 #  and can be added to the global gitignore or merged into this file.  For a more nuclear
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
 #.idea/
+.DS_Store
diff --git a/example.py b/example.py
index a28f326..25cfecc 100644
--- a/example.py
+++ b/example.py
@@ -12,7 +12,7 @@
 
 graph2 = dataset.get_named_graph("http://example.org/graph2")
 resource2 = graph2.create_resource()
-resource2.add_property(graph2.create_property("http://example.org/property3"), graph2.create_literal("Object2"))
+resource2.add_property(graph2.create_property("http://example.org/property3"), graph2.create_literal("Object2", language="da"))
 resource3 = graph2.create_resource("http://example.org/subject3")
 resource3.add_property(graph2.create_property("http://example.org/property4"), graph2.create_literal("Object3"))
 
diff --git a/oxijen/model_impl/impl.py b/oxijen/model_impl/impl.py
index 0acbc1c..cf96bb6 100644
--- a/oxijen/model_impl/impl.py
+++ b/oxijen/model_impl/impl.py
@@ -63,23 +63,26 @@ def create_resource(self, uri: Optional[str] = None) -> Resource:
     def create_property(self, uri: str) -> Property:
         return ResourceImpl(NamedNode(uri), self)
 
-    def create_literal(self, value: str) -> Literal:
-        return Literal(value) # should it be xsd:string-typed by default as per RDF 1.1?
+    def create_literal(self, value: str, language: Optional[str] = None) -> Literal:
+        return Literal(value, language=language) # should it be xsd:string-typed by default as per RDF 1.1?
 
-    def create_typed_literal(self, value: Any, type_uri: Optional[str] = None) -> Literal:
-        if type_uri is None:
+    def create_typed_literal(self, value: Any, datatype: Optional[Union[str, NamedNode]] = None) -> Literal:
+        if datatype is None:
             match value:
                 case int():
-                    type_uri = XSD.INTEGER.value
+                    datatype = NamedNode(XSD.INTEGER.value)
                 case str():
-                    type_uri = XSD.STRING.value
+                    datatype = NamedNode(XSD.STRING.value)
                 case float():
-                    type_uri = XSD.FLOAT.value
+                    datatype = NamedNode(XSD.FLOAT.value)
                 # TO-DO: support more types
                 case _:
                     raise TypeError('Unsupported type conversion')
+        else:
+            if type(datatype) is str:
+                datatype = NamedNode(datatype)
         
-        return Literal(str(value), datatype=NamedNode(type_uri))
+        return Literal(str(value), datatype=datatype)
 
 
 class GraphStoreImpl(GraphImpl):
@@ -105,6 +108,11 @@ def add(self, triples: Union[Iterator[Triple], 'Graph']) -> 'Graph':
 
         return self
 
+    def remove_all(self) -> 'Graph':
+        self.store.remove_graph(self.name)
+        
+        return self
+
 
 class DatasetStoreImpl(Dataset):
 
diff --git a/oxijen/rdf_model.py b/oxijen/rdf_model.py
index cf076db..81aae46 100644
--- a/oxijen/rdf_model.py
+++ b/oxijen/rdf_model.py
@@ -66,11 +66,11 @@ def create_property(self, uri: str) -> Property:
         pass
 
     @abstractmethod
-    def create_literal(self, value: str) -> Literal:
+    def create_literal(self, value: str, language: Optional[str] = None) -> Literal:
         pass
 
     @abstractmethod
-    def create_typed_literal(self, value: Any, type_uri: Optional[str] = None) -> Literal:
+    def create_typed_literal(self, value: Any, datatype: Optional[Union[str, NamedNode]] = None) -> Literal:
         pass
 
     @abstractmethod
@@ -81,6 +81,10 @@ def list_triples(self) -> Iterator[Triple]:
     def add(self, triples: Union[Iterator[Triple], 'Graph']) -> 'Graph':
         pass
 
+    @abstractmethod
+    def remove_all(self ) -> 'Graph':
+        pass
+
 
 class GraphFactory: