Fix section "MySQL Recovery" in section 12.4.md

Author: DeepAnchor

en/12.4.md

@@ -163,13 +163,14 @@ This sets up regular backups of your databases to the `/var/www/mysql` directory
 
 ## MySQL Recovery
 
-Earlier MySQL backup into hot backup and cold backup, hot backup main purpose is to be able to recover in real time, such as an application server hard disk failure occurred, then we can modify the database configuration file read and write into slave so that you can minimize the time interrupt service.
+We've just described some commonly used backup techniques for MySQL, namely hot backups and cold backups. To recap, the main goal of a hot backup is to be able to recover data in real-time after an application has failed in some way, such as in the case of a server hard-disk malfunction. We learned that this type of scheme can be implemented by modifying database configuration files so that databases are replicated onto a slave, minimizing interruption to services.   
 
 But sometimes we need to perform a cold backup of the SQL data recovery, as with database backup, you can import through the command:
+Hot backups are, however, sometimes inadequate. There are certain situations where cold backups are required to perform data recovery, even if it's only a partial one. When you have a cold backup of your database, you can use the following `MySQL` command to import it: 
 
 	mysql -u username -p databse < backup.sql
 
-You can see, export and import database data is fairly simple, but if you also need to manage permissions, or some other character set, it may be a little more complicated, but these can all be done through a number of commands.
+As you can see, importing and exporting database is a fairly simple matter. If you need to manage administrative privileges or deal with different character sets, this process may become a little more complicated, though there are a number of commands which will help you to do this.   
 
 ## Redis backup