diff --git a/fastNLP/api/api.py b/fastNLP/api/api.py
index c72f3690..351b210d 100644
--- a/fastNLP/api/api.py
+++ b/fastNLP/api/api.py
@@ -299,8 +299,8 @@ class CWS(API):
         te_dataset = reader.load(filepath)
         pp(te_dataset)
         
-        from fastNLP.core.tester import Tester
-        from fastNLP.core.metrics import BMESF1PreRecMetric
+        from ..core.tester import Tester
+        from ..core.metrics import BMESF1PreRecMetric
         
         tester = Tester(data=te_dataset, model=cws_model, metrics=BMESF1PreRecMetric(target='target'), batch_size=64,
                         verbose=0)
diff --git a/fastNLP/api/processor.py b/fastNLP/api/processor.py
index be111cd0..3c60e621 100644
--- a/fastNLP/api/processor.py
+++ b/fastNLP/api/processor.py
@@ -232,7 +232,7 @@ class SeqLenProcessor(Processor):
         return dataset
 
 
-from fastNLP.core.utils import _build_args
+from ..core.utils import _build_args
 
 
 class ModelProcessor(Processor):
diff --git a/fastNLP/core/vocabulary.py b/fastNLP/core/vocabulary.py
index aaaf84be..c82c316e 100644
--- a/fastNLP/core/vocabulary.py
+++ b/fastNLP/core/vocabulary.py
@@ -1,6 +1,6 @@
 from functools import wraps
 from collections import Counter
-from fastNLP.core.dataset import DataSet
+from .dataset import DataSet
 
 def _check_build_vocab(func):
     """A decorator to make sure the indexing is built before used.