diff --git a/fastNLP/core/metrics.py b/fastNLP/core/metrics.py
index 887a7abe..f75b6c90 100644
--- a/fastNLP/core/metrics.py
+++ b/fastNLP/core/metrics.py
@@ -737,7 +737,7 @@ def _pred_topk(y_prob, k=1):
 
 
 class ExtractiveQAMetric(MetricBase):
-    """
+    r"""
     别名：:class:`fastNLP.ExtractiveQAMetric` :class:`fastNLP.core.metrics.ExtractiveQAMetric`
 
     抽取式QA（如SQuAD）的metric.
diff --git a/fastNLP/io/data_loader/matching.py b/fastNLP/io/data_loader/matching.py
index 3f5759d6..21dcefb0 100644
--- a/fastNLP/io/data_loader/matching.py
+++ b/fastNLP/io/data_loader/matching.py
@@ -33,8 +33,8 @@ class MatchingLoader(DataSetLoader):
                 to_lower=False, seq_len_type: str=None, bert_tokenizer: str=None,
                 cut_text: int = None, get_index=True, auto_pad_length: int=None,
                 auto_pad_token: str='<pad>', set_input: Union[list, str, bool]=True,
-                set_target: Union[list, str, bool] = True, concat: Union[str, list, bool]=None, 
-                extra_split: List[str]=['-'], ) -> DataBundle:
+                set_target: Union[list, str, bool]=True, concat: Union[str, list, bool]=None,
+                extra_split: List[str]=List['-'], ) -> DataBundle:
         """
         :param paths: str或者Dict[str, str]。如果是str，则为数据集所在的文件夹或者是全路径文件名：如果是文件夹，
             则会从self.paths里面找对应的数据集名称与文件名。如果是Dict，则为数据集名称（如train、dev、test）和
diff --git a/fastNLP/io/data_loader/sst.py b/fastNLP/io/data_loader/sst.py
index ecbabd49..df46b47f 100644
--- a/fastNLP/io/data_loader/sst.py
+++ b/fastNLP/io/data_loader/sst.py
@@ -114,6 +114,9 @@ class SST2Loader(CSVLoader):
 
     def _load(self, path: str) -> DataSet:
         ds = super(SST2Loader, self)._load(path)
+        for k, v in self.field.items():
+            if k in ds.get_field_names():
+                ds.rename_field(k, v)
         ds.apply(lambda x: self.tokenizer(x[Const.INPUT]), new_field_name=Const.INPUT)
         print("all count:", len(ds))
         return ds
diff --git a/fastNLP/io/file_utils.py b/fastNLP/io/file_utils.py
index 04970cb3..cb762eb7 100644
--- a/fastNLP/io/file_utils.py
+++ b/fastNLP/io/file_utils.py
@@ -17,6 +17,10 @@ PRETRAINED_BERT_MODEL_DIR = {
     'en-large-uncased': 'bert-large-uncased-20939f45.zip',
     'en-large-cased': 'bert-large-cased-e0cf90fc.zip',
 
+    'en-large-cased-wwm': 'bert-large-cased-wwm-a457f118.zip',
+    'en-large-uncased-wwm': 'bert-large-uncased-wwm-92a50aeb.zip',
+    'en-base-cased-mrpc': 'bert-base-cased-finetuned-mrpc-c7099855.zip',
+
     'cn': 'bert-base-chinese-29d0a84a.zip',
     'cn-base': 'bert-base-chinese-29d0a84a.zip',
 
@@ -68,6 +72,7 @@ def cached_path(url_or_filename: str, cache_dir: Path=None) -> Path:
             "unable to parse {} as a URL or as a local path".format(url_or_filename)
         )
 
+
 def get_filepath(filepath):
     """
     如果filepath中只有一个文件，则直接返回对应的全路径
@@ -82,6 +87,7 @@ def get_filepath(filepath):
             return filepath
     return filepath
 
+
 def get_defalt_path():
     """
     获取默认的fastNLP存放路径, 如果将FASTNLP_CACHE_PATH设置在了环境变量中，将使用环境变量的值，使得不用每个用户都去下载。
@@ -98,6 +104,7 @@ def get_defalt_path():
     fastnlp_cache_dir = os.path.expanduser(os.path.join("~", ".fastNLP"))
     return fastnlp_cache_dir
 
+
 def _get_base_url(name):
     # 返回的URL结尾必须是/
     if 'FASTNLP_BASE_URL' in os.environ:
@@ -105,6 +112,7 @@ def _get_base_url(name):
         return fastnlp_base_url
     raise RuntimeError("There function is not available right now.")
 
+
 def split_filename_suffix(filepath):
     """
     给定filepath返回对应的name和suffix
@@ -116,6 +124,7 @@ def split_filename_suffix(filepath):
         return filename[:-7], '.tar.gz'
     return os.path.splitext(filename)
 
+
 def get_from_cache(url: str, cache_dir: Path = None) -> Path:
     """
     尝试在cache_dir中寻找url定义的资源; 如果没有找到。则从url下载并将结果放在cache_dir下，缓存的名称由url的结果推断而来。
@@ -226,6 +235,7 @@ def get_from_cache(url: str, cache_dir: Path = None) -> Path:
 
     return get_filepath(cache_path)
 
+
 def unzip_file(file: Path, to: Path):
     # unpack and write out in CoNLL column-like format
     from zipfile import ZipFile
@@ -234,13 +244,15 @@ def unzip_file(file: Path, to: Path):
         # Extract all the contents of zip file in current directory
         zipObj.extractall(to)
 
+
 def untar_gz_file(file:Path, to:Path):
     import tarfile
 
     with tarfile.open(file, 'r:gz') as tar:
         tar.extractall(to)
 
-def match_file(dir_name:str, cache_dir:str)->str:
+
+def match_file(dir_name: str, cache_dir: str) -> str:
     """
     匹配的原则是，在cache_dir下的文件: (1) 与dir_name完全一致; (2) 除了后缀以外和dir_name完全一致。
     如果找到了两个匹配的结果将报错. 如果找到了则返回匹配的文件的名称; 没有找到返回空字符串
@@ -261,6 +273,7 @@ def match_file(dir_name:str, cache_dir:str)->str:
     else:
         raise RuntimeError(f"Duplicate matched files:{matched_filenames}, this should be caused by a bug.")
 
+
 if __name__ == '__main__':
     cache_dir = Path('caches')
     cache_dir = None