diff --git a/Features.py b/Features.py
index dbf2953..41f83ef 100644
--- a/Features.py
+++ b/Features.py
@@ -8,6 +8,7 @@
 from NLPTreeHelper import containsSpan
 import sys
 import hminghkm as minghkm
+from pyglog import *
 
 class LocalFeatures:
   def __init__(self, pef, pfe):
@@ -98,6 +99,9 @@ def ff_identity(self, info, fWord, eWord, fIndex, eIndex, links, diagValues, cur
     name = self.ff_identity.func_name
     if len(links) == 1:
       link = links[0]
+      CHECK_GT(len(info['f']), 0, "Length of f sentence is 0.")
+      CHECK_GT(len(info['e']), 0, "Length of e sentence is 0.")
+
       if info['f'][link[0]] == info['e'][link[1]]:
         return {name: 1.0}
     return {name: 0.0}
diff --git a/README b/README
index 2b505d5..954eead 100644
--- a/README
+++ b/README
@@ -401,7 +401,7 @@ pages 1500-1511.
 Franz Josef Och and Hermann Ney. A Systematic Comparison of Various Statistical Alignment Models.
 Computational Linguistics, Volume 29, Number 1, pages 19-51. March 2003.
 
-Jason Riesa and Daniel Marcu. Hierarchical Seach for Word Alignment. 2010.
+Jason Riesa and Daniel Marcu. Hierarchical Search for Word Alignment. 2010.
 Proceedings of ACL, pages 157-166.
 
 Jason Riesa, Ann Irvine, and Daniel Marcu. Feature-Rich Language-Independent
diff --git a/nile.py b/nile.py
index 7b32f22..d702c7a 100755
--- a/nile.py
+++ b/nile.py
@@ -644,7 +644,7 @@ def do_training(indices, training_blob, heldout_blob, weights, weights_out, debi
     # copy the generic Features.py module to a file called
     # Features_ar_en.py and add your new feature functions
     # functions to the file. Then, just call nile with flag:
-    # --features ar_en
+    # --langpair ar_en
     # This will cause Nile to load module Features_ar_en.py
     # instead of the standard Features.py
     #
@@ -655,7 +655,6 @@ def do_training(indices, training_blob, heldout_blob, weights, weights_out, debi
         Features = __import__("Features_%s" % (FLAGS.langpair))
       except:
         if myRank == 0:
-          err_msg = "Language pair %s specified; " %(FLAGS.langpair)
           err_msg += "could not import language-specific features Features_%s.py. " %(FLAGS.langpair)
           err_msg += "Using standard featureset."
           LOG(INFO, err_msg)