Question pretext
Some people of your age have experimented with cigarette smoking, drinking alcohol and drug use. The questions that follow ask about your experiences with these things. Remember, your answers will not be linked to you.
Literal question
Think of all the times you have had a drink during the past 12 months. How many drinks did you usually have each time? (A “drink” is a glass of wine, a can of beer, a shot glass of liquor, or a mixed drink)