Suppose, Nazmul is your younger brother. He is not attentive to learn English. Now write an email to him advising him to be attentive to learn English.

 From       :sheuli78@gmail.com
To              :nazmul98@yahoo.com
Subject    :Advice to be attentive to learn English.

Dear Nazmul,
Hope you are well. I am very sorry to learn that you are not attentive to learn English. But my brother, don't you know that learning English is very important in the present world? Without learning English you cannot have higher education and a good job. Moreover, how can you make a good result without being attentive to English? So, I request you earnestly to be attentive to learn English.

With best wishes
Your elder sister
Sheuli