How to get back sent email???

In nepali there is saying as “Boleko Boli ra Haneko Goli” never comes back. This saying not only valid with the sound of person but also in the field of internet (while talking with each other).
In internet, nowadays there is different media through which you can directly send your message to the desired person. Among them Gmail service is one media provided by Google, from which you can send your email to the desired person. This service is counted as most used internet service for transferring news, message to peoples. Millions of people uses E-mail. Though it is used by millions of people. still there is lack of something that we need. Mainly, Google is unable to get back the message that is already sent to person for many years. But when Gmail introduces this facility millions of people were shocked and impressive. So in order to return back the sent email, people have got only 30 seconds. Within this 30 seconds, we can easily return back the sent email before the next person receive our email. If we were unable to return the sent email with 30 seconds, that can never be return.
So, how to??

For returning the sent email, when you compose the E-mail and click on sent button. You will notification on the top the windows. In that notification, after clicking the sent button, the countdown 30 seconds start. Until the countdown do not stop, you can easily return back that email by clicking on Undo second button.