Fix translation of summary for 12.4.md

Author: DeepAnchor

en/12.4.md

@@ -178,13 +178,13 @@ Redis is one of the most popular NoSQL databases, and both hot and cold backup t
 
 ## Redis recovery
 
-Similarly, Redis recovery can be divided into hot and cold backup recovery. The methods and objectives of recovering data from a hot backup of a Redis database  are the same as those mentioned above for MySQL, as long as the Redis application is using the appropriate database connection.   
+Similarly, Redis recovery can be divided into hot and cold backup recovery. The methods and objectives of recovering data from a hot backup of a Redis database are the same as those mentioned above for MySQL, as long as the Redis application is using the appropriate database connection.   
 
 A Redis cold backup recovery simply involves copying backed-up database files into the working directory, then starting Redis on it. The database files are automatically loaded into memory at boot time; the speed with which Redis boots will depend on the size of the database files. 
 
 ## Summary
 
-This section describes the application of part of our backup and recovery, that is, how to do disaster recovery, including file backup, database backup. Also introduced different systems using rsync file synchronization, MySQL database and Redis database backup and recovery, hope that through the introduction of this section, you can give as a developer of products for online disaster recovery program provides a reference solution.
+In this section, we looked at some techniques for backing up data as well as recovering from disasters, after deploying our applications. We also introduced rsync, a tool which can be used to synchronize files on different systems. Using rsync, we can easily perform backup and restoration procedures for both MySQL and Redis databases, among others. We hope that by being introduced to some of these concepts, you will be able to develop disaster recovery procedures to better protect the data in your web applications.  
 
 ## Links