diff --git a/lab_4_fill_words_by_ngrams/main.py b/lab_4_fill_words_by_ngrams/main.py
index b739ae182..1fe19ee9c 100644
--- a/lab_4_fill_words_by_ngrams/main.py
+++ b/lab_4_fill_words_by_ngrams/main.py
@@ -4,6 +4,8 @@
 Top-p sampling generation and filling gaps with ngrams
 """
 # pylint:disable=too-few-public-methods, too-many-arguments
+from random import choice
+
 from lab_3_generate_by_ngrams.main import (BeamSearchTextGenerator, GreedyTextGenerator,
                                            NGramLanguageModel, TextProcessor)
 
@@ -28,6 +30,19 @@ def _tokenize(self, text: str) -> tuple[str, ...]:  # type: ignore
         Raises:
             ValueError: In case of inappropriate type input argument or if input argument is empty.
         """
+        if not isinstance(text, str) or not text:
+            raise ValueError('Type input is inappropriate or input argument is empty.')
+
+        tokens = []
+        punctuation_signs = '?!.'
+        for word in text.lower().split():
+            cleaned_word = [letter for letter in word if letter.isalpha()]
+            if not cleaned_word:
+                continue
+            tokens.append(''.join(cleaned_word))
+            if word[-1] in punctuation_signs:
+                tokens.append(self._end_of_word_token)
+        return tuple(tokens)
 
     def _put(self, element: str) -> None:
         """
@@ -39,6 +54,11 @@ def _put(self, element: str) -> None:
         Raises:
             ValueError: In case of inappropriate type input argument or if input argument is empty.
         """
+        if not isinstance(element, str) or not element:
+            raise ValueError('Type input is inappropriate or input argument is empty.')
+
+        if element not in self._storage:
+            self._storage[element] = len(self._storage)
 
     def _postprocess_decoded_text(self, decoded_corpus: tuple[str, ...]) -> str:  # type: ignore
         """
@@ -56,6 +76,16 @@ def _postprocess_decoded_text(self, decoded_corpus: tuple[str, ...]) -> str:  #
         Raises:
             ValueError: In case of inappropriate type input argument or if input argument is empty.
         """
+        if not isinstance(decoded_corpus, tuple) or not decoded_corpus:
+            raise ValueError('Type input is inappropriate or input argument is empty.')
+
+        words = " ".join(decoded_corpus)
+        sentences = words.split(self._end_of_word_token)
+        resulted_text = ". ".join([sentence.strip().capitalize() for sentence in sentences])
+
+        if resulted_text[-1] == ' ':
+            return resulted_text[:-1]
+        return f"{resulted_text}."
 
 
 class TopPGenerator:
@@ -80,6 +110,9 @@ def __init__(
             word_processor (WordProcessor): WordProcessor instance to handle text processing
             p_value (float): Collective probability mass threshold
         """
+        self._model = language_model
+        self._word_processor = word_processor
+        self._p_value = p_value
 
     def run(self, seq_len: int, prompt: str) -> str:  # type: ignore
         """
@@ -98,6 +131,40 @@ def run(self, seq_len: int, prompt: str) -> str:  # type: ignore
                 or if sequence has inappropriate length,
                 or if methods used return None.
         """
+        if not (isinstance(seq_len, int) and isinstance(prompt, str) and
+                seq_len > 0 and prompt):
+            raise ValueError('Type input is inappropriate or input argument is empty.')
+
+        encoded_prompt = self._word_processor.encode(prompt)
+        if encoded_prompt is None:
+            raise ValueError('None is returned')
+
+        encoded_list = list(encoded_prompt)
+        for i in range(seq_len):
+            candidates = self._model.generate_next_token(encoded_prompt)
+            if candidates is None:
+                raise ValueError('None is returned.')
+            if not candidates:
+                break
+            sorted_candidates = sorted(list(candidates.items()),
+                                       key=lambda pair: (pair[1], pair[0]), reverse=True)
+            sum_freq = 0
+            num_candidates = 0
+            for _, freq in sorted_candidates:
+                if sum_freq >= self._p_value:
+                    break
+                sum_freq += freq
+                num_candidates += 1
+
+            random_token = choice(sorted_candidates[:num_candidates])[0]
+            encoded_list.append(random_token)
+            encoded_prompt = tuple(encoded_list)
+
+        decoded = self._word_processor.decode(encoded_prompt)
+        if decoded is None:
+            raise ValueError('None is returned')
+
+        return decoded
 
 
 class GeneratorTypes:
diff --git a/lab_4_fill_words_by_ngrams/start.py b/lab_4_fill_words_by_ngrams/start.py
index c41386377..a9d6d93ad 100644
--- a/lab_4_fill_words_by_ngrams/start.py
+++ b/lab_4_fill_words_by_ngrams/start.py
@@ -2,6 +2,7 @@
 Filling word by ngrams starter
 """
 # pylint:disable=too-many-locals,unused-import
+from lab_4_fill_words_by_ngrams.main import NGramLanguageModel, TopPGenerator, WordProcessor
 
 
 def main() -> None:
@@ -10,7 +11,15 @@ def main() -> None:
     """
     with open("./assets/Harry_Potter.txt", "r", encoding="utf-8") as text_file:
         text = text_file.read()
-    result = None
+    word_processor = WordProcessor("<eos>")
+    encoded_text = word_processor.encode(text)
+    lang_model = NGramLanguageModel(encoded_text, 2)
+    lang_model.build()
+
+    top_p_generator = TopPGenerator(lang_model, word_processor, 0.5)
+    result = top_p_generator.run(51, "Vernon")
+    print(result)
+
     assert result
 
 
diff --git a/lab_4_fill_words_by_ngrams/target_score.txt b/lab_4_fill_words_by_ngrams/target_score.txt
index 573541ac9..1e8b31496 100644
--- a/lab_4_fill_words_by_ngrams/target_score.txt
+++ b/lab_4_fill_words_by_ngrams/target_score.txt
@@ -1 +1 @@
-0
+6