diff --git a/analyse/analyse.go b/analyse/analyse.go
index c61d4b2..c7412e9 100644
--- a/analyse/analyse.go
+++ b/analyse/analyse.go
@@ -1,6 +1,7 @@
 package analyse
 
 import (
+	//	"fmt"
 	"github.com/wangbin/jiebago"
 	"sort"
 	"strings"
@@ -8,10 +9,14 @@ import (
 )
 
 type TfIdf struct {
-	word string
-	freq float64
+	Word string
+	Freq float64
 }
 
+//func (t TfIdf) String() string {
+//	return fmt.Sprintf("{%s: %f}", t.Word, t.Freq)
+//}
+
 type TfIdfs []TfIdf
 
 func (tis TfIdfs) Len() int {
@@ -19,17 +24,18 @@ func (tis TfIdfs) Len() int {
 }
 
 func (tis TfIdfs) Less(i, j int) bool {
-	if tis[i].freq == tis[j].freq {
-		return tis[i].word < tis[j].word
+	if tis[i].Freq == tis[j].Freq {
+		return tis[i].Word < tis[j].Word
 	}
-	return tis[i].freq < tis[j].freq
+
+	return tis[i].Freq < tis[j].Freq
 }
 
 func (tis TfIdfs) Swap(i, j int) {
 	tis[i], tis[j] = tis[j], tis[i]
 }
 
-func ExtractTags(sentence string, topK int) []string {
+func ExtractTags(sentence string, topK int) (tags TfIdfs) {
 	words := jiebago.Cut(sentence, false, true)
 	freq := make(map[string]float64)
 
@@ -58,22 +64,17 @@ func ExtractTags(sentence string, topK int) []string {
 	for k, v := range freq {
 		var ti TfIdf
 		if freq_, ok := idfLoader.Freq[k]; ok {
-			ti = TfIdf{word: k, freq: freq_ * v}
+			ti = TfIdf{Word: k, Freq: freq_ * v}
 		} else {
-			ti = TfIdf{word: k, freq: idfLoader.Median * v}
+			ti = TfIdf{Word: k, Freq: idfLoader.Median * v}
 		}
 		tis = append(tis, ti)
 	}
 	sort.Sort(sort.Reverse(tis))
-	var topTfIdfs TfIdfs
 	if len(tis) > topK {
-		topTfIdfs = tis[:topK]
+		tags = tis[:topK]
 	} else {
-		topTfIdfs = tis
-	}
-	tags := make([]string, len(topTfIdfs))
-	for index, ti := range topTfIdfs {
-		tags[index] = ti.word
+		tags = tis
 	}
 	return tags
 }
diff --git a/analyse/analyse_test.go b/analyse/analyse_test.go
index e375152..f1dc9ed 100644
--- a/analyse/analyse_test.go
+++ b/analyse/analyse_test.go
@@ -2,6 +2,7 @@ package analyse
 
 import (
 	"github.com/wangbin/jiebago"
+	"math"
 	"testing"
 )
 
@@ -180,6 +181,65 @@ var (
 		[]string{"的士", "的哥", "他开", "握手", "一辆", "黑色", "主席", "认识", "那个"},
 		[]string{"枪杆子", "政权"},
 	}
+
+	Lyric = `
+我沒有心
+我沒有真實的自我
+我只有消瘦的臉孔
+所謂軟弱
+所謂的順從一向是我
+的座右銘
+
+而我
+沒有那海洋的寬闊
+我只要熱情的撫摸
+所謂空洞
+所謂不安全感是我
+的墓誌銘
+
+而你
+是否和我一般怯懦
+是否和我一般矯作
+和我一般囉唆
+
+而你
+是否和我一般退縮
+是否和我一般肌迫
+一般地困惑
+
+我沒有力
+我沒有滿腔的熱火
+我只有滿肚的如果
+所謂勇氣
+所謂的認同感是我
+隨便說說
+
+而你
+是否和我一般怯懦
+是否和我一般矯作
+是否對你來說
+只是一場遊戲
+雖然沒有把握
+
+而你
+是否和我一般退縮
+是否和我一般肌迫
+是否對你來說
+只是逼不得已
+雖然沒有藉口
+`
+	LyciWeight = []TfIdf{
+		TfIdf{Word: "所謂", Freq: 1.010262},
+		TfIdf{Word: "是否", Freq: 0.738650},
+		TfIdf{Word: "一般", Freq: 0.607600},
+		TfIdf{Word: "雖然", Freq: 0.336754},
+		TfIdf{Word: "退縮", Freq: 0.336754},
+		TfIdf{Word: "肌迫", Freq: 0.336754},
+		TfIdf{Word: "矯作", Freq: 0.336754},
+		TfIdf{Word: "沒有", Freq: 0.336754},
+		TfIdf{Word: "怯懦", Freq: 0.271099},
+		TfIdf{Word: "隨便", Freq: 0.168377},
+	}
 )
 
 func TestExtractTags(t *testing.T) {
@@ -192,10 +252,21 @@ func TestExtractTags(t *testing.T) {
 			t.Errorf("%s = %v", sentence, result)
 		}
 		for i, tag := range result {
-			if tag != Tags[index][i] {
+			if tag.Word != Tags[index][i] {
 				t.Errorf("%s != %s", tag, Tags[index][i])
 			}
 		}
 	}
-
+}
+
+func TestExtratTagsWithWeight(t *testing.T) {
+	jiebago.SetDictionary("../dict.txt")
+	SetIdf("idf.txt")
+	result := ExtractTags(Lyric, 10)
+	for index, tag := range result {
+		if LyciWeight[index].Word != tag.Word ||
+			math.Abs(LyciWeight[index].Freq-tag.Freq) > 1e-6 {
+			t.Errorf("%v != %v", tag, LyciWeight[index])
+		}
+	}
 }