diff --git a/analyse/idf.go b/analyse/idf.go
index eeaed53..e4250b4 100644
--- a/analyse/idf.go
+++ b/analyse/idf.go
@@ -10,45 +10,11 @@ import (
 )
 
 var (
-	stopWords map[string]string
 	idfLoader *IDFLoader
 )
 
 func init() {
 	idfLoader = NewIDFLoader()
-	stopWords = map[string]string{
-		"the":   "the",
-		"of":    "of",
-		"is":    "is",
-		"and":   "and",
-		"to":    "to",
-		"in":    "in",
-		"that":  "that",
-		"we":    "we",
-		"for":   "for",
-		"an":    "an",
-		"are":   "are",
-		"by":    "bye",
-		"be":    "be",
-		"as":    "as",
-		"on":    "on",
-		"with":  "with",
-		"can":   "can",
-		"if":    "of",
-		"from":  "from",
-		"which": "which",
-		"you":   "you",
-		"it":    "it",
-		"this":  "this",
-		"then":  "then",
-		"at":    "at",
-		"have":  "have",
-		"all":   "all",
-		"not":   "not",
-		"one":   "one",
-		"has":   "has",
-		"or":    "or",
-	}
 }
 
 type IDFLoader struct {
@@ -103,27 +69,3 @@ func SetIdf(idfFilePath string) error {
 	}
 	return idfLoader.NewPath(idfFilePath)
 }
-
-func SetStopWords(stopWordsFilePath string) error {
-	if !filepath.IsAbs(stopWordsFilePath) {
-		pwd, err := os.Getwd()
-		if err != nil {
-			return err
-		}
-		stopWordsFilePath = filepath.Clean(filepath.Join(pwd, stopWordsFilePath))
-	}
-	stopWordsFile, err := os.Open(stopWordsFilePath)
-	if err != nil {
-		return err
-	}
-	scanner := bufio.NewScanner(stopWordsFile)
-	for scanner.Scan() {
-		stopWord := scanner.Text()
-		stopWord = strings.TrimSpace(stopWord)
-		stopWords[stopWord] = stopWord
-	}
-	if err := scanner.Err(); err != nil {
-		return err
-	}
-	return nil
-}
diff --git a/analyse/stopwords.go b/analyse/stopwords.go
new file mode 100644
index 0000000..c6d4d1a
--- /dev/null
+++ b/analyse/stopwords.go
@@ -0,0 +1,70 @@
+package analyse
+
+import (
+	"bufio"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+var stopWords map[string]string
+
+func init() {
+	stopWords = map[string]string{
+		"the":   "the",
+		"of":    "of",
+		"is":    "is",
+		"and":   "and",
+		"to":    "to",
+		"in":    "in",
+		"that":  "that",
+		"we":    "we",
+		"for":   "for",
+		"an":    "an",
+		"are":   "are",
+		"by":    "bye",
+		"be":    "be",
+		"as":    "as",
+		"on":    "on",
+		"with":  "with",
+		"can":   "can",
+		"if":    "of",
+		"from":  "from",
+		"which": "which",
+		"you":   "you",
+		"it":    "it",
+		"this":  "this",
+		"then":  "then",
+		"at":    "at",
+		"have":  "have",
+		"all":   "all",
+		"not":   "not",
+		"one":   "one",
+		"has":   "has",
+		"or":    "or",
+	}
+}
+
+func SetStopWords(stopWordsFilePath string) error {
+	if !filepath.IsAbs(stopWordsFilePath) {
+		pwd, err := os.Getwd()
+		if err != nil {
+			return err
+		}
+		stopWordsFilePath = filepath.Clean(filepath.Join(pwd, stopWordsFilePath))
+	}
+	stopWordsFile, err := os.Open(stopWordsFilePath)
+	if err != nil {
+		return err
+	}
+	scanner := bufio.NewScanner(stopWordsFile)
+	for scanner.Scan() {
+		stopWord := scanner.Text()
+		stopWord = strings.TrimSpace(stopWord)
+		stopWords[stopWord] = stopWord
+	}
+	if err := scanner.Err(); err != nil {
+		return err
+	}
+	return nil
+}