diff --git a/Project_Model/Libs/BPE/Classes/NanoSocratesBPE.py b/Project_Model/Libs/BPE/Classes/NanoSocratesBPE.py
index 844e860..c7f89ce 100644
--- a/Project_Model/Libs/BPE/Classes/NanoSocratesBPE.py
+++ b/Project_Model/Libs/BPE/Classes/NanoSocratesBPE.py
@@ -1,11 +1,16 @@
 from .Encoder import Encoder
-from ..Errors import OutOfDictionaryException
+from ..Errors import OutOfDictionaryException, DuplicateWordException
 
 
 class NanoSocratesBatchMemoryBPE:
 
-    def __init__(self) -> None:
-        pass
+    def __init__(
+        self,
+        frequencies: dict[tuple[int, int], int],
+        merge_treshold: int
+    ) -> None:
+        self.frequencies = frequencies
+        self.merge_treshold = merge_treshold
 
 
 class NanoSocratesBPE(Encoder):
@@ -22,12 +27,66 @@ class NanoSocratesBPE(Encoder):
         for key, value in vocabulary.items():
             if value < 256:
                 raise OutOfDictionaryException()
+            # TODO: check if they are in order
             self.__vocabulary[key] = value
             self.__reverse_vocabulary[value] = key
 
+
+    @property
+    def vocabulary_size(self):
+        return len(self.__vocabulary) + 255
+
+    @property
+    def vocabulary(self):
+        return self.__vocabulary
+
+    @property
+    def __next_id(self):
+        return self.vocabulary_size + 1
+
     # TODO: implement fit
-    def fit():
-        pass
+    def fit(
+        self,
+        chunk_data: list[int],
+        memory: NanoSocratesBatchMemoryBPE,
+        last_batch: bool
+    ):
+
+        ENCODED_CHUNK = self.__round_encode(chunk_data)
+        DATA_LEN_BEFORE_LAST = len(ENCODED_CHUNK) - 1
+
+        for i in range(0, DATA_LEN_BEFORE_LAST):
+            CANDIDATE_COUPLE = (ENCODED_CHUNK[i], ENCODED_CHUNK[i+1])
+
+            frequency = memory.frequencies.get(CANDIDATE_COUPLE)
+
+            # Initialize frequency
+            if frequency is None:
+                frequency = 0
+                memory.frequencies[CANDIDATE_COUPLE] = 0
+
+            frequency += 1
+            memory.frequencies[CANDIDATE_COUPLE] = frequency
+
+        if not last_batch:
+            return (self, memory, ENCODED_CHUNK)
+
+        if len(memory.frequencies) < 1:
+            return (self, memory, ENCODED_CHUNK)
+
+        FREQUENCIES = memory.frequencies
+        MAX_COUPLE = max(FREQUENCIES.items(), key=lambda item: item[1])[0]
+        FREQUENCY = FREQUENCIES[MAX_COUPLE]
+
+        if FREQUENCY < memory.merge_treshold:
+            return (self, memory, ENCODED_CHUNK)
+
+        self.__learn_word(MAX_COUPLE)
+
+        return (self, memory, ENCODED_CHUNK)
+
+
+
 
     def encode(self, piece: str) -> list[int]:
 
@@ -104,3 +163,15 @@ class NanoSocratesBPE(Encoder):
             raise OutOfDictionaryException()
 
         return CANDIDATE_DECODED
+
+    def __learn_word(self, words: tuple[int, int]):
+
+        ID = self.__next_id
+
+        DUPLICATE = self.__vocabulary.get(words)
+
+        if DUPLICATE is not None:
+            raise DuplicateWordException()
+
+        self.__vocabulary[words] = ID
+        self.__reverse_vocabulary[ID] = words