diff --git a/BotSharp.Algorithm/Extensions/Split.cs b/BotSharp.Algorithm/Extensions/Split.cs
new file mode 100644
index 00000000..5f53058f
--- /dev/null
+++ b/BotSharp.Algorithm/Extensions/Split.cs
@@ -0,0 +1,24 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace BotSharp.Algorithm.Extensions
+{
+    public static partial class IListExtensions
+    {
+        /// <summary>
+        /// Split dataset to training and test part.
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="list"></param>
+        /// <param name="percentage">must between 0 and 1</param>
+        /// <returns></returns>
+        public static Tuple<List<T>, List<T>> Split<T>(this IList<T> list, decimal percentage)
+        {
+            int boundary = int.Parse(Math.Floor(list.Count * percentage).ToString());
+
+            return new Tuple<List<T>, List<T>>(list.Take(boundary).ToList(), list.Skip(boundary).ToList());
+        }
+    }
+}
diff --git a/BotSharp.NLP.UnitTest/NaiveBayesClassifierTest.cs b/BotSharp.NLP.UnitTest/NaiveBayesClassifierTest.cs
index d4a037ca..44979a00 100644
--- a/BotSharp.NLP.UnitTest/NaiveBayesClassifierTest.cs
+++ b/BotSharp.NLP.UnitTest/NaiveBayesClassifierTest.cs
@@ -15,6 +15,42 @@ namespace BotSharp.NLP.UnitTest
     [TestClass]
     public class NaiveBayesClassifierTest : TestEssential
     {
+        [TestMethod]
+        public void CookingTest()
+        {
+            var reader = new FasttextDataReader();
+            var sentences = reader.Read(new ReaderOptions
+            {
+                DataDir = Path.Combine(Configuration.GetValue<String>("MachineLearning:dataDir"), "Text Classification", "cooking.stackexchange"),
+                FileName = "cooking.stackexchange.txt"
+            });
+
+            var tokenizer = new TokenizerFactory<TreebankTokenizer>(new TokenizationOptions { }, SupportedLanguage.English);
+            sentences.ForEach(x => x.Words = tokenizer.Tokenize(x.Text));
+
+            sentences.Shuffle();
+
+            var options = new ClassifyOptions
+            {
+                TrainingCorpusDir = Path.Combine(Configuration.GetValue<String>("MachineLearning:dataDir"), "Text Classification", "cooking.stackexchange")
+            };
+            var classifier = new ClassifierFactory<NaiveBayesClassifier>(options, SupportedLanguage.English);
+            var dataset = sentences.Split(0.7M);
+            classifier.Train(dataset.Item1);
+
+            int correct = 0;
+            dataset.Item2.ForEach(td =>
+            {
+                var classes = classifier.Classify(td);
+                if (td.Label == classes[0].Item1)
+                {
+                    correct++;
+                }
+            });
+
+            var accuracy = (float)correct / dataset.Item2.Count;
+        }
+
         [TestMethod]
         public void GenderTest()
         {
@@ -45,7 +81,7 @@ namespace BotSharp.NLP.UnitTest
             testData.ForEach(td =>
             {
                 var classes = classifier.Classify(td);
-                if(td.Labels[0] == classes[0].Item1)
+                if(td.Label == classes[0].Item1)
                 {
                     correct++;
                 }
diff --git a/BotSharp.NLP/Classify/ClassifierFactory.cs b/BotSharp.NLP/Classify/ClassifierFactory.cs
index 3baba28a..24df05e2 100644
--- a/BotSharp.NLP/Classify/ClassifierFactory.cs
+++ b/BotSharp.NLP/Classify/ClassifierFactory.cs
@@ -38,7 +38,7 @@ namespace BotSharp.NLP.Classify
         {
             _classifier.Train(sentences.Select(x => new LabeledFeatureSet
             {
-                Label = x.Labels[0],
+                Label = x.Label,
                 Features = GetFeatures(x.Words)
             }).ToList(), _options);
         }
diff --git a/BotSharp.NLP/Corpus/FasttextDataReader.cs b/BotSharp.NLP/Corpus/FasttextDataReader.cs
index 87a6e6f1..92306a24 100644
--- a/BotSharp.NLP/Corpus/FasttextDataReader.cs
+++ b/BotSharp.NLP/Corpus/FasttextDataReader.cs
@@ -14,6 +14,11 @@ namespace BotSharp.NLP.Corpus
     {
         public List<Sentence> Read(ReaderOptions options)
         {
+            if (String.IsNullOrEmpty(options.LabelPrefix))
+            {
+                options.LabelPrefix = "__label__";
+            }
+
             var sentences = new List<Sentence>();
             using (StreamReader reader = new StreamReader(Path.Combine(options.DataDir, options.FileName)))
             {
@@ -22,13 +27,21 @@ namespace BotSharp.NLP.Corpus
                     string line = reader.ReadLine();
                     if (!String.IsNullOrEmpty(line))
                     {
-                        var ms = Regex.Matches(line, @"__label__\w+\s").Cast<Match>().ToList();
+                        var ms = Regex.Matches(line, options.LabelPrefix + @"\S+")
+                            .Cast<Match>()
+                            .ToList();
 
-                        sentences.Add(new Sentence
+                        var text = line.Substring(ms.Last().Index + ms.Last().Length + 1);
+
+                        ms.ForEach(m =>
                         {
-                            // Label = lable,
-                            Text = line
+                            sentences.Add(new Sentence
+                            {
+                                Label = m.Value.Substring(options.LabelPrefix.Length),
+                                Text = text
+                            });
                         });
+
                     }
                 }
             }
diff --git a/BotSharp.NLP/Corpus/LabeledPerFileNameReader.cs b/BotSharp.NLP/Corpus/LabeledPerFileNameReader.cs
index 1a9eb3b7..17bf3cab 100644
--- a/BotSharp.NLP/Corpus/LabeledPerFileNameReader.cs
+++ b/BotSharp.NLP/Corpus/LabeledPerFileNameReader.cs
@@ -14,7 +14,7 @@ namespace BotSharp.NLP.Corpus
     {
         public List<Sentence> Read(ReaderOptions options)
         {
-            string lable = options.FileName.Split('.')[0];
+            string label = options.FileName.Split('.')[0];
 
             var sentences = new List<Sentence>();
             using (StreamReader reader = new StreamReader(Path.Combine(options.DataDir, options.FileName)))
@@ -26,7 +26,7 @@ namespace BotSharp.NLP.Corpus
                     {
                         sentences.Add(new Sentence
                         {
-                            Labels = new List<string> { lable },
+                            Label = label,
                             Text = line
                         });
                     }
diff --git a/BotSharp.NLP/Corpus/ReaderOptions.cs b/BotSharp.NLP/Corpus/ReaderOptions.cs
index 29229c7d..b60f6101 100644
--- a/BotSharp.NLP/Corpus/ReaderOptions.cs
+++ b/BotSharp.NLP/Corpus/ReaderOptions.cs
@@ -9,5 +9,7 @@ namespace BotSharp.NLP.Corpus
         public string DataDir { get; set; }
 
         public string FileName { get; set; }
+
+        public string LabelPrefix { get; set; }
     }
 }
diff --git a/BotSharp.NLP/Sentence.cs b/BotSharp.NLP/Sentence.cs
index 50d075d6..e0914fa4 100644
--- a/BotSharp.NLP/Sentence.cs
+++ b/BotSharp.NLP/Sentence.cs
@@ -9,10 +9,7 @@ namespace BotSharp.NLP
     {
         public List<Token> Words { get; set; }
 
-        /// <summary>
-        /// Allow multiple classification
-        /// </summary>
-        public List<String> Labels { get; set; }
+        public String Label { get; set; }
 
         public String Text { get; set; }
     }
diff --git a/BotSharp.NLP/Tokenize/Token.cs b/BotSharp.NLP/Tokenize/Token.cs
index 35f71d5e..c11cd3ed 100644
--- a/BotSharp.NLP/Tokenize/Token.cs
+++ b/BotSharp.NLP/Tokenize/Token.cs
@@ -52,7 +52,7 @@ namespace BotSharp.NLP.Tokenize
         {
             get
             {
-                return Start + Text.Length - 1;
+                return Start + Text.Length;
             }
         }
 
diff --git a/BotSharp.NLP/Tokenize/TreebankTokenizer.cs b/BotSharp.NLP/Tokenize/TreebankTokenizer.cs
index d820f215..25bebc89 100644
--- a/BotSharp.NLP/Tokenize/TreebankTokenizer.cs
+++ b/BotSharp.NLP/Tokenize/TreebankTokenizer.cs
@@ -128,7 +128,7 @@ namespace BotSharp.NLP.Tokenize
                 var token = tokens[i];
                 token.Start = sentence.IndexOf(token.Text, startPos);
 
-                startPos = token.End + 1;
+                startPos = token.End;
             }
         }