diff --git a/core/query_formatter.py b/core/query_formatter.py
index 437f316..b592324 100644
--- a/core/query_formatter.py
+++ b/core/query_formatter.py
@@ -222,6 +222,9 @@ def format_expression(node: Node):
         return node.name
     
     elif node.type == NodeType.LITERAL:
+        if isinstance(node.value, str):
+            return {'literal': node.value}
+
         return node.value
     
     elif node.type == NodeType.FUNCTION:
@@ -230,6 +233,10 @@ def format_expression(node: Node):
         args = [format_expression(arg) for arg in node.children]
         return {func_name: args[0] if len(args) == 1 else args}
     
+    elif node.type == NodeType.SUBQUERY:
+        subquery_node = list(node.children)[0]
+        return ast_to_json(subquery_node)
+    
     elif node.type == NodeType.OPERATOR:
         # format: {'operator': [left, right]}
         op_map = {
diff --git a/tests/test_query_formatter.py b/tests/test_query_formatter.py
index 2fe2c56..f3f3dae 100644
--- a/tests/test_query_formatter.py
+++ b/tests/test_query_formatter.py
@@ -5,17 +5,10 @@
     OrderByNode, LimitNode, OffsetNode, SubqueryNode, VarNode, VarSetNode, JoinNode
 )
 from core.ast.enums import JoinType, SortOrder
-from re import sub
+from mo_sql_parsing import parse
 
 formatter = QueryFormatter()
 
-def normalize_sql(s):
-    """Remove extra whitespace and normalize SQL string to be used in comparisons"""
-    s = s.strip()
-    s = sub(r'\s+', ' ', s)
-    
-    return s
-
 def test_basic_format():
     # Construct expected AST
     # Tables
@@ -82,7 +75,7 @@ def test_basic_format():
     sql = formatter.format(ast)
     sql = sql.strip()
     
-    assert normalize_sql(sql) == normalize_sql(expected_sql)
+    assert parse(sql) == parse(expected_sql)
 
 
 def test_subquery_format():
@@ -142,9 +135,9 @@ def test_subquery_format():
         )
         AND 1 = 1
     """
-    # expected_sql = expected_sql.strip()
+    expected_sql = expected_sql.strip()
     
-    # sql = formatter.format(ast)
-    # sql = sql.strip()
+    sql = formatter.format(ast)
+    sql = sql.strip()
     
-    # assert normalize_sql(sql) == normalize_sql(expected_sql)
\ No newline at end of file
+    assert parse(sql) == parse(expected_sql)
\ No newline at end of file