diff --git a/tokenization_chatglm.py b/tokenization_chatglm.py
index 1d4f0ba..69ee85c 100644
--- a/tokenization_chatglm.py
+++ b/tokenization_chatglm.py
@@ -31,6 +31,9 @@ class TextTokenizer:
     def tokenize(self, text):
         return self.sp.EncodeAsPieces(text)
 
+    def convert_tokens_to_string(self, tokens):
+        return self.sp.DecodePieces(tokens)
+
     def convert_tokens_to_ids(self, tokens):
         return [self.sp.PieceToId(token) for token in tokens]
 
@@ -111,16 +114,25 @@ class SPTokenizer:
         tokens = [x + self.num_image_tokens for x in tmp]
         return tokens if add_dummy_prefix else tokens[2:]
 
-    def decode(self, text_ids: List[int]) -> str:
-        ids = [int(_id) - self.num_image_tokens for _id in text_ids]
-        ids = [_id for _id in ids if _id >= 0]
-        text = self._get_text_tokenizer().decode(ids)
+    def postprocess(self, text):
         text = text.replace("<n>", "\n")
         text = text.replace(SPTokenizer.get_tab_token(), "\t")
         for i in range(2, self.max_blank_length + 1):
             text = text.replace(self.get_blank_token(i), " " * i)
         return text
 
+    def decode(self, text_ids: List[int]) -> str:
+        ids = [int(_id) - self.num_image_tokens for _id in text_ids]
+        ids = [_id for _id in ids if _id >= 0]
+        text = self._get_text_tokenizer().decode(ids)
+        text = self.postprocess(text)
+        return text
+
+    def decode_tokens(self, tokens: List[str]) -> str:
+        text = self._get_text_tokenizer().convert_tokens_to_string(tokens)
+        text = self.postprocess(text)
+        return text
+
     def tokenize(
             self, text: str, linebreak=True, whitespaces=True, add_dummy_prefix=True
     ) -> List[str]:
@@ -256,11 +268,12 @@ class ChatGLMTokenizer(PreTrainedTokenizer):
 
         return seq
 
+    def convert_tokens_to_string(self, tokens: List[str]) -> str:
+        return self.sp_tokenizer.decode_tokens(tokens)
+
     def _decode(
             self,
             token_ids: Union[int, List[int]],
-            skip_special_tokens: bool = False,
-            clean_up_tokenization_spaces: bool = True,
             **kwargs
     ) -> str:
         if isinstance(token_ids, int):
@@ -269,7 +282,7 @@ class ChatGLMTokenizer(PreTrainedTokenizer):
             return ""
         if self.pad_token_id in token_ids:  # remove pad
             token_ids = list(filter((self.pad_token_id).__ne__, token_ids))
-        return self.sp_tokenizer.decode(token_ids)
+        return super()._decode(token_ids, **kwargs)
 
     def _convert_token_to_id(self, token):
         """ Converts a token (str) in an id using the vocab. """