diff --git a/jieba/__init__.py b/jieba/__init__.py
index 2bc5b41..0b1dcad 100644
--- a/jieba/__init__.py
+++ b/jieba/__init__.py
@@ -157,7 +157,7 @@ def cut(sentence,cut_all=False):
 		except:
 			sentence = sentence.decode('gbk','ignore')
 
-	re_han, re_skip = re.compile("([\u4E00-\u9FA5a-zA-Z0-9+#&\.]+)"), re.compile("(\s+)")
+	re_han, re_skip = re.compile("([\u4E00-\u9FA5a-zA-Z0-9+#&\._]+)"), re.compile("(\s+)")
 
 	if cut_all:
 		re_han, re_skip = re.compile("([\u4E00-\u9FA5]+)"), re.compile("[^a-zA-Z0-9+#\n]")
@@ -175,7 +175,8 @@ def cut(sentence,cut_all=False):
 			tmp = re_skip.split(blk)
 			for x in tmp:
 				if re_skip.match(x):
-					yield x
+					if x.strip(' ')!='':
+						yield x
 				else:
 					for xx in x:
 						yield xx
diff --git a/jieba/dict.txt b/jieba/dict.txt
index f4b81ef..3fbcb4a 100644
--- a/jieba/dict.txt
+++ b/jieba/dict.txt
@@ -245161,10 +245161,9 @@
 皂隶 96 n
 皂靴 10 n
 皂鞋 3 n
-的 3188252 uj
+的 318825 uj
 的一确二 3 l
 的士高 3 n
-的歌者 3 n
 的的确确 64 d
 的确 2135 d
 的确如此 31 l
@@ -245174,6 +245173,8 @@
 的里雅斯特 23 ns
 的里雅斯特市 3 ns
 的黎波里 62 ns
+的哥 63 n
+的士 20 n
 皆 7511 d
 皆佳 3 nrt
 皆准 3 i
diff --git a/jieba/posseg/__init__.py b/jieba/posseg/__init__.py
index d4e93cf..c1933f2 100644
--- a/jieba/posseg/__init__.py
+++ b/jieba/posseg/__init__.py
@@ -129,7 +129,7 @@ def cut(sentence):
 		except:
 			sentence = sentence.decode('gbk','ignore')
 
-	re_han, re_skip = re.compile("([\u4E00-\u9FA5a-zA-Z0-9+#&\.]+)"), re.compile("(\s+)")
+	re_han, re_skip = re.compile("([\u4E00-\u9FA5a-zA-Z0-9+#&\._]+)"), re.compile("(\s+)")
 	re_eng,re_num = re.compile("[a-zA-Z0-9]+"), re.compile("[\.0-9]+")
 
 	blocks = re_han.split(sentence)
@@ -141,7 +141,8 @@ def cut(sentence):
 			tmp = re_skip.split(blk)
 			for x in tmp:
 				if re_skip.match(x):
-					yield pair(x,'')
+					if x.strip(' ')!='':
+						yield pair(x,'')
 				else:
 					for xx in x:
 						if re_num.match(xx):
diff --git a/test/test.py b/test/test.py
index 8fed235..e69a218 100644
--- a/test/test.py
+++ b/test/test.py
@@ -92,3 +92,4 @@ if __name__ == "__main__":
 	cuttest('张晓梅去人民医院做了个B超然后去买了件T恤')
 	cuttest('AT&T是一件不错的公司，给你发offer了吗？')
 	cuttest('C++和c#是什么关系？11+122=133，是吗？PI=3.14159')
+	cuttest('你认识那个和主席握手的的哥吗？他开一辆黑色的士。')
diff --git a/test/test_pos.py b/test/test_pos.py
index 01b77e0..1268321 100644
--- a/test/test_pos.py
+++ b/test/test_pos.py
@@ -94,4 +94,4 @@ if __name__ == "__main__":
 	cuttest('张晓梅去人民医院做了个B超然后去买了件T恤')
 	cuttest('AT&T是一件不错的公司，给你发offer了吗？')
 	cuttest('C++和c#是什么关系？11+122=133，是吗？PI=3.14159')
-
+	cuttest('你认识那个和主席握手的的哥吗？他开一辆黑色的士。')
diff --git a/test/test_userdict.py b/test/test_userdict.py
index 4e7b49b..f94be41 100644
--- a/test/test_userdict.py
+++ b/test/test_userdict.py
@@ -14,3 +14,13 @@ result = pseg.cut(test_sent)
 
 for w in result:
 	print(w.word, "/", w.flag, ", ")
+
+print("\n========")
+
+terms = jieba.cut('easy_install is great')
+for t in terms:
+    print(t)
+print('-------------------------')
+terms = jieba.cut('python 的正则表达式是好用的')
+for t in terms:
+    print(t)
diff --git a/test/userdict.txt b/test/userdict.txt
index 56e1f3d..4632566 100644
--- a/test/userdict.txt
+++ b/test/userdict.txt
@@ -1,3 +1,5 @@
-云计算 5
+云计算 5
 李小福 2 nr
-创新办 3 i
\ No newline at end of file
+创新办 3 i
+easy_install 3 eng
+好用 300
\ No newline at end of file