diff --git a/dict.go b/dict.go
index f133cc4..0149fc6 100644
--- a/dict.go
+++ b/dict.go
@@ -8,6 +8,7 @@ import (
 	"strings"
 )
 
+// DefaultMinTokenLen is default minimum tokenLen
 var DefaultMinTokenLen = 2
 
 // DictRecord records dict meta info
diff --git a/minimum_matching.go b/minimum_matching.go
index 089dcf8..8cedac9 100644
--- a/minimum_matching.go
+++ b/minimum_matching.go
@@ -4,11 +4,13 @@ import (
 	"strings"
 )
 
+// MinMatch records dict and dictPath
 type MinMatch struct {
 	dict     *Dict
 	dictPath string
 }
 
+// NewMinMatch returns a newly initialized MinMatch object
 func NewMinMatch(dictPath string) *MinMatch {
 	return &MinMatch{
 		dictPath: dictPath,
diff --git a/tokenizer.go b/tokenizer.go
index 35cbe4e..7e2d621 100644
--- a/tokenizer.go
+++ b/tokenizer.go
@@ -1,5 +1,6 @@
 package gotokenizer
 
+// Tokenizer defines interface of Tokenizer
 type Tokenizer interface {
 	GetFrequency(text string) (map[string]int, error)
 	Get(text string) ([]string, error)