diff --git a/test/pbt_rb_tree_monoid_test.exs b/test/pbt_rb_tree_monoid_test.exs
index 07d1f53..19789d9 100644
--- a/test/pbt_rb_tree_monoid_test.exs
+++ b/test/pbt_rb_tree_monoid_test.exs
@@ -5,7 +5,7 @@ defmodule RedBlackTreeMonoidPropertyTest do
 
   property "merging with nil (neutral element) does not change the tree" do
     check all(
-            keys <- uniq_list_of(integer()),
+            keys <- uniq_list_of(integer(), min_length: 1, max_tries: 1000),
             values <- list_of(term()),
             max_runs: 50
           ) do
@@ -24,11 +24,11 @@ defmodule RedBlackTreeMonoidPropertyTest do
 
   property "associative property of merging two trees" do
     check all(
-            keys1 <- uniq_list_of(integer(), min_length: 1, max_length: 20),
+            keys1 <- uniq_list_of(integer(), min_length: 1, max_tries: 1000),
             values1 <- list_of(term(), length: length(keys1)),
-            keys2 <- uniq_list_of(integer(), min_length: 1, max_length: 20),
+            keys2 <- uniq_list_of(integer(), min_length: 1, max_tries: 1000),
             values2 <- list_of(term(), length: length(keys2)),
-            keys3 <- uniq_list_of(integer(), min_length: 1, max_length: 20),
+            keys3 <- uniq_list_of(integer(), min_length: 1, max_tries: 1000),
             values3 <- list_of(term(), length: length(keys3)),
             max_runs: 100
           ) do
diff --git a/test/pbt_tree_dict_test.exs b/test/pbt_tree_dict_test.exs
new file mode 100644
index 0000000..789db7c
--- /dev/null
+++ b/test/pbt_tree_dict_test.exs
@@ -0,0 +1,47 @@
+defmodule TreeDictTreePropertyBasedTest do
+  use ExUnit.Case
+  use ExUnitProperties
+
+  alias RedBlackTree
+
+  property "insert and get values correctly" do
+    check all(key <- term(), value <- term()) do
+      dict = TreeDict.new() |> TreeDict.insert(key, value)
+      assert TreeDict.get(dict, key) == value
+    end
+  end
+
+  property "deleting a key removes it from the dictionary" do
+    check all(key <- term(), value <- term()) do
+      dict = TreeDict.new() |> TreeDict.insert(key, value) |> TreeDict.delete(key)
+      assert TreeDict.get(dict, key) == nil
+    end
+  end
+
+  property "merging two dictionaries maintains values" do
+    check all(
+            keys1 <- uniq_list_of(integer(), min_length: 1),
+            keys2 <- uniq_list_of(integer(), min_length: 1),
+            values1 <- list_of(term(), length: length(keys1)),
+            values2 <- list_of(term(), length: length(keys2))
+          ) do
+      dict1 =
+        Enum.zip(keys1, values1)
+        |> Enum.reduce(TreeDict.new(), fn {k, v}, acc -> TreeDict.insert(acc, k, v) end)
+
+      dict2 =
+        Enum.zip(keys2, values2)
+        |> Enum.reduce(TreeDict.new(), fn {k, v}, acc -> TreeDict.insert(acc, k, v) end)
+
+      merged_dict = TreeDict.merge(dict1, dict2)
+
+      Enum.each(keys1, fn k ->
+        if k in keys2 do
+          assert TreeDict.get(merged_dict, k) != nil
+        else
+          assert TreeDict.get(merged_dict, k) == TreeDict.get(dict1, k)
+        end
+      end)
+    end
+  end
+end
diff --git a/test/unit_tree_dict_test.exs b/test/unit_tree_dict_test.exs
index d8f96b5..4252154 100644
--- a/test/unit_tree_dict_test.exs
+++ b/test/unit_tree_dict_test.exs
@@ -127,4 +127,75 @@ defmodule TreeDictTest do
     assert TreeDict.get(dict, :b) == nil
     assert TreeDict.get(dict, :c) == nil
   end
+
+  test "filtering keys based on value" do
+    dict = TreeDict.new()
+    dict = TreeDict.insert(dict, :key1, 10)
+    dict = TreeDict.insert(dict, :key2, 20)
+    dict = TreeDict.insert(dict, :key3, 30)
+
+    filtered_dict = TreeDict.filter(dict, fn _key, value -> value > 15 end)
+
+    assert TreeDict.get(filtered_dict, :key1) == nil
+    assert TreeDict.get(filtered_dict, :key2) == 20
+    assert TreeDict.get(filtered_dict, :key3) == 30
+  end
+
+  # Тесты на отображение (map)
+  test "applying map function to all values" do
+    dict = TreeDict.new()
+    dict = TreeDict.insert(dict, :key1, 10)
+    dict = TreeDict.insert(dict, :key2, 20)
+    dict = TreeDict.insert(dict, :key3, 30)
+
+    mapped_dict = TreeDict.map(dict, fn _key, value -> value * 2 end)
+
+    assert TreeDict.get(mapped_dict, :key1) == 20
+    assert TreeDict.get(mapped_dict, :key2) == 40
+    assert TreeDict.get(mapped_dict, :key3) == 60
+  end
+
+  # Тесты на свёртки (левая и правая)
+  test "left fold applies function from left to right" do
+    dict = TreeDict.new()
+    dict = TreeDict.insert(dict, 1, 2)
+    dict = TreeDict.insert(dict, 3, 4)
+    dict = TreeDict.insert(dict, 5, 6)
+
+    result = TreeDict.foldl(dict, 0, fn _key, value, acc -> acc + value end)
+    assert result == 12
+  end
+
+  test "right fold applies function from right to left" do
+    dict = TreeDict.new()
+    dict = TreeDict.insert(dict, 1, 2)
+    dict = TreeDict.insert(dict, 3, 4)
+    dict = TreeDict.insert(dict, 5, 6)
+
+    result = TreeDict.foldr(dict, 0, fn _key, value, acc -> acc + value end)
+    assert result == 12
+  end
+
+  # Check monoid properties
+  test "monoid property: merging with empty TreeDict" do
+    dict1 = TreeDict.new()
+    dict2 = TreeDict.insert(TreeDict.new(), :key, "value")
+
+    merged_left = TreeDict.merge(dict1, dict2)
+    merged_right = TreeDict.merge(dict2, dict1)
+
+    assert merged_left == dict2
+    assert merged_right == dict2
+  end
+
+  test "monoid property: associative merging" do
+    dict1 = TreeDict.insert(TreeDict.new(), :key1, "value1")
+    dict2 = TreeDict.insert(TreeDict.new(), :key2, "value2")
+    dict3 = TreeDict.insert(TreeDict.new(), :key3, "value3")
+
+    merged_left = TreeDict.merge(TreeDict.merge(dict1, dict2), dict3)
+    merged_right = TreeDict.merge(dict1, TreeDict.merge(dict2, dict3))
+
+    assert merged_left == merged_right
+  end
 end