diff --git a/iobber/chunker.py b/iobber/chunker.py
index 616029bfb546801718b919dad50004b0928ab2d4..16ed3437d37209634a326148d0ee6c1a2a75018e 100644
--- a/iobber/chunker.py
+++ b/iobber/chunker.py
@@ -138,6 +138,7 @@ class Chunker:
 					class_label = corpus2.to_string(chan.get_iob_at(tok_idx))
 					# generate training example and store to file
 					classify.write_example(tr_file, feat_vals, class_label)
+				classify.write_end_of_sent(tr_file)
 			
 			self.stats.num_sents += 1
 			self.stats.num_toks += sent.tokens().size()
diff --git a/iobber/classify.py b/iobber/classify.py
index f70a7762b8c28e275bf54b925d195367439fdb59..bce6a1da74dcef9fc8f074e6fc8efbcd604cb560 100644
--- a/iobber/classify.py
+++ b/iobber/classify.py
@@ -38,6 +38,10 @@ def write_example(tr_file, feat_vals, class_label):
 	tr_file.write(class_label)
 	tr_file.write('\n')
 
+def write_end_of_sent(tr_file):
+	"""Writes end-of-sentence marker to the training file."""
+	tr_file.write('\n')
+
 def train_and_save(conf, model_name, config_dir, data_dir, chan_name):
 	"""Trains a CRF classifier for the given chan_name. The trained model
 	is saved to filenames (generated using model_name and conf)."""