diff --git a/src/examples/indefinites/util.py b/src/examples/indefinites/util.py
index 735b245e..9275905d 100644
--- a/src/examples/indefinites/util.py
+++ b/src/examples/indefinites/util.py
@@ -16,7 +16,7 @@
 from .meaning import universe as indefinites_universe
 
 
-def read_natural_languages(filename: str) -> list[Language]:
+def read_natural_languages(filename: str) -> set[Language]:
     """Read the natural languages from a CSV file.
     Assumes that each row is one expression, with unique strings in "language" column identifying
     which expressions belong to which languages.
@@ -48,12 +48,12 @@ def read_natural_languages(filename: str) -> list[Language]:
             # add Expression with form and Meaning
             cur_expressions.append(Expression(item.expression, cur_meaning))
         # add Language with its Expressions
-        languages.add(Language(cur_expressions, name=lang, natural=True))
+        languages.add(Language(tuple(cur_expressions), name=lang, natural=True))
     return languages
 
 
 def read_expressions(
-    filename: str, universe: Universe = None, return_by_meaning=True
+    filename: str, universe: Universe | None = None, return_by_meaning=True
 ) -> tuple[list[GrammaticalExpression], dict[Meaning, Expression]]:
     """Read expressions from a YAML file.
     Assumes that the file is a list, and that each item in the list has a field
@@ -77,10 +77,10 @@ def read_expressions(
 def write_languages(
     languages: list[Language],
     filename: str,
-    properties_to_add: dict[str, Callable[[int, Language], Any]] = None,
+    properties_to_add: dict[str, Callable[[int, Language], Any]] = {},
 ) -> None:
     lang_dicts = [
-        language.to_dict(
+        language.as_dict_with_properties(
             **{key: properties_to_add[key](idx, language) for key in properties_to_add}
         )
         for idx, language in enumerate(languages)
diff --git a/src/ultk/language/grammar.py b/src/ultk/language/grammar.py
index 9c3516cc..ae831d6a 100644
--- a/src/ultk/language/grammar.py
+++ b/src/ultk/language/grammar.py
@@ -106,7 +106,7 @@ def add_child(self, child) -> None:
             self.children = self.children + (child,)
 
     def to_dict(self) -> dict:
-        the_dict = super().to_dict()
+        the_dict = super().__dict__
         the_dict["grammatical_expression"] = str(self)
         the_dict["length"] = len(self)
         return the_dict
diff --git a/src/ultk/language/language.py b/src/ultk/language/language.py
index 5cb3fed8..469da60c 100644
--- a/src/ultk/language/language.py
+++ b/src/ultk/language/language.py
@@ -33,9 +33,6 @@ def can_express(self, referent: Referent) -> bool:
         """Return True if the expression can express the input single meaning point and false otherwise."""
         return referent in self.meaning.referents
 
-    def to_dict(self) -> dict:
-        return {"form": self.form, "meaning": self.meaning.to_dict()}
-
     def __str__(self) -> str:
         return self.form
         # return f"Expression {self.form}\nMeaning:\n\t{self.meaning}"
@@ -116,7 +113,10 @@ def universe(self) -> Universe:
     def universe(self, val) -> None:
         self._universe = val
 
-    def to_dict(self, **kwargs) -> dict:
+    def as_dict_with_properties(self, **kwargs) -> dict:
+        """Return a dictionary representation of the language, including additional properties as keyword arguments.
+
+        This is used in some examples to serialize the language to outputs."""
         the_dict = {"expressions": [str(expr) for expr in self.expressions]}
         the_dict.update(kwargs)
         return the_dict
diff --git a/src/ultk/language/semantics.py b/src/ultk/language/semantics.py
index 196d064c..95850c3a 100644
--- a/src/ultk/language/semantics.py
+++ b/src/ultk/language/semantics.py
@@ -47,9 +47,6 @@ def __setattr__(self, __name: str, __value: Any) -> None:
         else:
             object.__setattr__(self, __name, __value)
 
-    def to_dict(self) -> dict:
-        return self.__dict__
-
     def __str__(self) -> str:
         return str(self.__dict__)
 
@@ -181,9 +178,6 @@ def dist(self) -> tuple:
                 for idx in range(len(self.universe.referents))
             )
 
-    def to_dict(self) -> dict:
-        return {"referents": [referent.to_dict() for referent in self.referents]}
-
     def __bool__(self):
         return bool(self.referents) and bool(self.universe)