diff --git a/src/parse_tree/parse_tree.py b/src/parse_tree/parse_tree.py
index b601f81..39beb61 100644
--- a/src/parse_tree/parse_tree.py
+++ b/src/parse_tree/parse_tree.py
@@ -1,44 +1,49 @@
-import warnings
-from typing import List, Dict
+from typing import List, Dict, Optional
 
-from anytree import Node, RenderTree
+from anytree import RenderTree
 
-from src.parse_tree.parse_tree_item import ParseItem
+from src.parse_tree.parse_tree_node import ParseTreeNode
 
 
 class ParseTree:
 
     def __init__(self, raw_tree: str):
-        self._tree: Node = self.__create_tree(self.__create_nodes_array(raw_tree))
+        self._tree: ParseTreeNode = self.__create_tree(self.__create_nodes_array(raw_tree))
 
     @staticmethod
-    def __create_nodes_array(raw_tree: str) -> List[ParseItem]:
-        nodes: List[ParseItem] = []
+    def __parse_raw_tree_line(raw_tree_line: str) -> Optional[ParseTreeNode]:
+        parsed_str = raw_tree_line.split('\t')
+        if len(parsed_str) != 10:
+            return None
+        return ParseTreeNode(int(parsed_str[0]), parsed_str[1], parsed_str[3], int(parsed_str[6]), parsed_str[7])
+
+    def __create_nodes_array(self, raw_tree: str) -> List[ParseTreeNode]:
+        nodes: List[ParseTreeNode] = []
         parsed_syntax_lines = raw_tree.split('\n')
         for line in parsed_syntax_lines:
-            try:
-                nodes.append(ParseItem(line))
-            except AssertionError:
-                warnings.warn('Empty line')
+            tree_node = self.__parse_raw_tree_line(line)
+            if tree_node:
+                nodes.append(tree_node)
         return nodes
 
-    def __create_tree(self, nodes: List[ParseItem]) -> Node:
+    @staticmethod
+    def __create_tree(nodes: List[ParseTreeNode]) -> ParseTreeNode:
         tree_nodes_count: int = 0
-        parents: Dict[int, Node] = {}
-        root = None
+        parents: Dict[int, ParseTreeNode] = {}
+        root: ParseTreeNode = Optional[ParseTreeNode]
         while tree_nodes_count < len(nodes):
             for node in nodes:
-                if parents.get(node.index()) is not None:
+                if parents.get(node.index) is not None:
                     continue
-                parent: Node = parents.get(node.parent_index())
-                if parent is not None or node.parent_index() == 0:
-                    new_node = Node(node, parent)
-                    parents[node.index()] = new_node
+                parent: ParseTreeNode = parents.get(node.parent_index)
+                if parent is not None or node.parent_index == 0:
+                    node.parent = parent
+                    parents[node.index] = node
                     tree_nodes_count = tree_nodes_count + 1
-                    if node.parent_index() == 0:
-                        root = new_node
+                    if node.parent_index == 0:
+                        root = node
                     break
         return root
 
     def __repr__(self) -> str:
-        return '\n'.join([f'{pre}{node.name}' for pre, fill, node in RenderTree(self._tree)])
+        return '\n'.join([f'{pre}{node}' for pre, fill, node in RenderTree(self._tree)])
diff --git a/src/parse_tree/parse_tree_item.py b/src/parse_tree/parse_tree_item.py
deleted file mode 100644
index 79bd4d4..0000000
--- a/src/parse_tree/parse_tree_item.py
+++ /dev/null
@@ -1,22 +0,0 @@
-class ParseItem:
-    def __init__(self, syntax_result_line: str):
-        parsed_str = syntax_result_line.split('\t')
-        if len(parsed_str) != 10:
-            raise AssertionError(f'{syntax_result_line} is not CoNNL-U-2 line')
-        self._index: int = int(parsed_str[0])
-        self._lemma: str = parsed_str[1]
-        self._upos: str = parsed_str[3]
-        self._parent_index: int = int(parsed_str[6])
-        self._relation: str = parsed_str[7]
-
-    def index(self) -> int:
-        return self._index
-
-    def parent_index(self) -> int:
-        return self._parent_index
-
-    def __repr__(self) -> str:
-        return f'{self._index} {self._lemma} {self._upos} {self._parent_index} {self._relation}'
-
-
-
diff --git a/src/parse_tree/parse_tree_node.py b/src/parse_tree/parse_tree_node.py
new file mode 100644
index 0000000..d0aa55a
--- /dev/null
+++ b/src/parse_tree/parse_tree_node.py
@@ -0,0 +1,20 @@
+from anytree import NodeMixin
+
+
+class ParseTreeNode(NodeMixin):
+
+    def __init__(self, index: int, lemma: str, upos: str, parent_index: int, relation: str, parent=None, children=None):
+        self.index = index
+        self.lemma = lemma
+        self.upos = upos
+        self.parent_index = parent_index
+        self.relation = relation
+        self.parent = parent
+        if children:
+            self.children = children
+
+    def __repr__(self) -> str:
+        return f'{self.index} {self.lemma} {self.upos} {self.parent_index} {self.relation}'
+
+
+
diff --git a/src/speech.py b/src/speech.py
index 885e495..f391b71 100644
--- a/src/speech.py
+++ b/src/speech.py
@@ -3,6 +3,7 @@ from scipy.io import wavfile
 
 
 class Speech:
+
     @staticmethod
     def __check_wav(wav_file):
         sample_rate, sig = wavfile.read(wav_file)