Write a Letter to your younger brother warning him against the dangers of drug-addiction. 

Simla
Aug .13, 20xx 
Dear Rohan, 
Last right I witnessed a tellyprogramme highlighting the abuse of drugs. It made me think of you. I believe you are aware of the fact that many students take drugs like smack (heroin). They want to have some pleasure or want to escape boredom, frustration and mental tension. But soon they become addicted to drugs. They smoke them or have them injected into their blood. This is harmful to the body and leads to a painful death. Sometimes an injection infects a man with a deadly AIDS virus which kills him. 

I hope you will take my advice and avoid the company of drug addicts. 
Yours affectionately 
Shekhar