diff --git a/src/bin/dhcp4/tests/ctrl_dhcp4_srv_unittest.cc b/src/bin/dhcp4/tests/ctrl_dhcp4_srv_unittest.cc
index d901779203..cff5d5cd57 100644
--- a/src/bin/dhcp4/tests/ctrl_dhcp4_srv_unittest.cc
+++ b/src/bin/dhcp4/tests/ctrl_dhcp4_srv_unittest.cc
@@ -811,9 +811,10 @@ TEST_F(CtrlChannelDhcpv4SrvTest, configSet) {
     // Verify the control channel socket no longer exists.
     EXPECT_FALSE(fileExists(socket_path_));
 
-    // With no command channel, should still receive the response. The config contains random
-    // socket name (/tmp/kea-<value-changing-each-time>/kea4.sock), so the
-    // hash will be different each time. As such, we can do simplified checks:
+    // With no command channel, should still receive the response.
+    // The config contains random socket name
+    // (/tmp/kea-<value-changing-each-time>/kea4.sock), so the hash will
+    // be different each time. As such, we can do simplified checks:
     // - verify the "result": 0 is there
     // - verify the "text": "Configuration successful." is there
     EXPECT_NE(response.find("\"result\": 0"), std::string::npos);
@@ -868,7 +869,7 @@ TEST_F(CtrlChannelDhcpv4SrvTest, configHashGet) {
     int status;
     ConstElementPtr args = parseAnswer(status, rsp);
     EXPECT_EQ(CONTROL_RESULT_SUCCESS, status);
-    // the parseAnswer is trying to be smart with ignoring hash.
+    // The parseAnswer is trying to be smart with ignoring hash.
     // But this time we really want to see the hash, so we'll retrieve
     // the arguments manually.
     args = rsp->get(CONTROL_ARGUMENTS);
diff --git a/src/bin/dhcp4/tests/http_control_socket_unittest.cc b/src/bin/dhcp4/tests/http_control_socket_unittest.cc
index daee3a3b66..5bebc44970 100644
--- a/src/bin/dhcp4/tests/http_control_socket_unittest.cc
+++ b/src/bin/dhcp4/tests/http_control_socket_unittest.cc
@@ -263,7 +263,7 @@ public:
     /// @param response_str a string containing the whole HTTP
     /// response received.
     ///
-    /// @return An HttpResponse constructed from parsing the response string.
+    /// @return An HttpResponse constructed by parsing the response string.
     HttpResponsePtr parseResponse(const std::string response_str) {
         HttpResponsePtr hr(new HttpResponse());
         HttpResponseParser parser(*hr);
@@ -299,8 +299,8 @@ public:
         ASSERT_TRUE(client);
 
         // Send the command. This will trigger server's handler which receives
-        // data over the HTTP socket. The server will start sending
-        // response to the client.
+        // data over the HTTP socket. The server will start sending response
+        // to the client.
         ASSERT_NO_THROW(client->startRequest(buildPostStr(command)));
         runIOService();
         ASSERT_TRUE(client->receiveDone());
diff --git a/src/bin/dhcp6/tests/ctrl_dhcp6_srv_unittest.cc b/src/bin/dhcp6/tests/ctrl_dhcp6_srv_unittest.cc
index 700995ce0d..78fb384175 100644
--- a/src/bin/dhcp6/tests/ctrl_dhcp6_srv_unittest.cc
+++ b/src/bin/dhcp6/tests/ctrl_dhcp6_srv_unittest.cc
@@ -726,7 +726,7 @@ TEST_F(CtrlChannelDhcpv6SrvTest, configSet) {
     EXPECT_FALSE(fileExists(socket_path_));
 
     // With no command channel, should still receive the response.
-    // The config contains random socket name socket name
+    // The config contains random socket name
     // (/tmp/kea-<value-changing-each-time>/kea6.sock), so the hash will
     // be different each time. As such, we can do simplified checks:
     // - verify the "result": 0 is there