diff --git a/data_utils/audio.py b/data_utils/audio.py
index 1f75da8ac3afdb5f04acc664d377ce01e82b1b48..3c671b69b80227e71a22a6b4c119d1d3e5e49e69 100755
--- a/data_utils/audio.py
+++ b/data_utils/audio.py
@@ -88,7 +88,8 @@ class AudioSegment(object):
         :rtype: AudioSegment
         :raises ValueError: If the number of segments is zero, or if the 
                             sample_rate of any two segments does not match.
-        :raises TypeError: If every segment in is not Audiosegment instance.
+        :raises TypeError: If every item in segments is not Audiosegment
+                           instance.
         """
         # Perform basic sanity-checks.
         if len(segments) == 0:
diff --git a/data_utils/speech.py b/data_utils/speech.py
index 443df68c631a5888755dc2dd3cedc4fca7afed82..66f22b24712fb4f25d5a98202ab617bbc2bbe340 100755
--- a/data_utils/speech.py
+++ b/data_utils/speech.py
@@ -75,7 +75,8 @@ class SpeechSegment(AudioSegment):
         :rtype: SpeechSegment
         :raises ValueError: If the number of segments is zero, or if the 
                             sample_rate of any two segments does not match.
-        :raises TypeError: If every segment in is not Audiosegment instance.
+        :raises TypeError: If every item in segments is not Audiosegment
+                           instance.
         """
         if len(segments) == 0:
             raise ValueError("No audio segments are given to concatenate.")