diff --git a/cluster/cluster_impl/available_cluster.go b/cluster/cluster_impl/available_cluster.go
index b70a97fad2de1b267ac1c6a5f0672ff445fadcc3..ebd5767e4c320f10c8911cf9ac3f2c81deaafb0e 100644
--- a/cluster/cluster_impl/available_cluster.go
+++ b/cluster/cluster_impl/available_cluster.go
@@ -38,6 +38,7 @@ func NewAvailableCluster() cluster.Cluster {
 	return &availableCluster{}
 }
 
+// Join returns a baseClusterInvoker instance
 func (cluser *availableCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return NewAvailableClusterInvoker(directory)
 }
diff --git a/cluster/cluster_impl/broadcast_cluster.go b/cluster/cluster_impl/broadcast_cluster.go
index 024cf4f533b91937ca998136d48e6b147bab03b7..ea3dee921888baa8f997cd02e92ee582f09a37d5 100644
--- a/cluster/cluster_impl/broadcast_cluster.go
+++ b/cluster/cluster_impl/broadcast_cluster.go
@@ -39,7 +39,7 @@ func NewBroadcastCluster() cluster.Cluster {
 	return &broadcastCluster{}
 }
 
-// Join would return baseClusterInvoker instance
+// Join returns a baseClusterInvoker instance
 func (cluster *broadcastCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return newBroadcastClusterInvoker(directory)
 }
diff --git a/cluster/cluster_impl/failback_cluster.go b/cluster/cluster_impl/failback_cluster.go
index 589b6bfc46993ba680a0eaa11fba6d45306dd865..278ac5432e7db5d8379e4aba81065ff2ab704ff5 100644
--- a/cluster/cluster_impl/failback_cluster.go
+++ b/cluster/cluster_impl/failback_cluster.go
@@ -39,7 +39,7 @@ func NewFailbackCluster() cluster.Cluster {
 	return &failbackCluster{}
 }
 
-// Join would return baseClusterInvoker instance
+// Join returns a baseClusterInvoker instance
 func (cluster *failbackCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return newFailbackClusterInvoker(directory)
 }
diff --git a/cluster/cluster_impl/failfast_cluster.go b/cluster/cluster_impl/failfast_cluster.go
index d8b7e9543bd7e02f9aef20530f3e5dbf3076a0f1..a5ea7a05855e58b9db02f41fcfba83b52d35d8b0 100644
--- a/cluster/cluster_impl/failfast_cluster.go
+++ b/cluster/cluster_impl/failfast_cluster.go
@@ -39,7 +39,7 @@ func NewFailFastCluster() cluster.Cluster {
 	return &failfastCluster{}
 }
 
-// Join would return baseClusterInvoker instance
+// Join returns a baseClusterInvoker instance
 func (cluster *failfastCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return newFailFastClusterInvoker(directory)
 }
diff --git a/cluster/cluster_impl/failover_cluster.go b/cluster/cluster_impl/failover_cluster.go
index ecc3596f8ac4602ad8508bfdc99726688e61e6d5..254cc097e3e7f0cc70dfcff01212562bc6febe97 100644
--- a/cluster/cluster_impl/failover_cluster.go
+++ b/cluster/cluster_impl/failover_cluster.go
@@ -40,7 +40,7 @@ func NewFailoverCluster() cluster.Cluster {
 	return &failoverCluster{}
 }
 
-// Join would return baseClusterInvoker instance
+// Join returns a baseClusterInvoker instance
 func (cluster *failoverCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return newFailoverClusterInvoker(directory)
 }
diff --git a/cluster/cluster_impl/failsafe_cluster.go b/cluster/cluster_impl/failsafe_cluster.go
index 25f42dd0a9d534f904f73ba97ae6174c3b954aec..d9465c034cb9e76d2f360b395f17b23d9234c532 100644
--- a/cluster/cluster_impl/failsafe_cluster.go
+++ b/cluster/cluster_impl/failsafe_cluster.go
@@ -39,7 +39,7 @@ func NewFailsafeCluster() cluster.Cluster {
 	return &failsafeCluster{}
 }
 
-// Join would return baseClusterInvoker instance
+// Join returns a baseClusterInvoker instance
 func (cluster *failsafeCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return newFailsafeClusterInvoker(directory)
 }
diff --git a/cluster/cluster_impl/forking_cluster.go b/cluster/cluster_impl/forking_cluster.go
index 9dd366d0b5b31f538b16d42ecbcff4bd4854f425..8c9911327527e66864200630f5a52dd5c7b9be53 100644
--- a/cluster/cluster_impl/forking_cluster.go
+++ b/cluster/cluster_impl/forking_cluster.go
@@ -39,7 +39,7 @@ func NewForkingCluster() cluster.Cluster {
 	return &forkingCluster{}
 }
 
-// Join would return baseClusterInvoker instance
+// Join returns a baseClusterInvoker instance
 func (cluster *forkingCluster) Join(directory cluster.Directory) protocol.Invoker {
 	return newForkingClusterInvoker(directory)
 }
diff --git a/cluster/router/tag/tag_router.go b/cluster/router/tag/tag_router.go
index 74f51075c7896177884e16f9736ebcf21262f112..e1376fd96a88246e7ad0e26d2e3c34693c88a77c 100644
--- a/cluster/router/tag/tag_router.go
+++ b/cluster/router/tag/tag_router.go
@@ -38,7 +38,7 @@ type tagRouter struct {
 	priority int64
 }
 
-// NewTagRouter would return tagRouter instance if url is not nil
+// NewTagRouter returns a tagRouter instance if url is not nil
 func NewTagRouter(url *common.URL) (*tagRouter, error) {
 	if url == nil {
 		return nil, perrors.Errorf("Illegal route URL!")