1. Drinking diet soda could be dangerous to your health.

2. What is diet soda ?
Diet sodas are typically sugar-free, artificially sweetened and non-alcoholic carbonated beverages. They are generally marketed toward health-conscious people, diabetics, athletes, and other people who want to lose weight, improve physical fitness, or reduce their sugar intake.

3. Questions:
1.What is the reason that Drinking diet soda could be dangerous to our health?
2.How many times can we drink diet soda for a week?
3.What kind of bad thing in diet soda?
4.What's your opinion for drinking?

4. History of diet soda
The beginning of the diet soda or refreshment era was in 1952, when Kirsch Bottling in Brooklyn, New York launched a sugar- free ginger ale called No-Cal. It was designed for diabetics, not dieters, and distribution remained local.
In 1963, the Coca-Cola Company joined the diet soda market with Tab, which proved to be a huge success. Tab was originally sweetened with cyclamates and saccharin.

5. New Words: 1.celeries n.芹菜（celery的复数形式）
2.sensational adj. causing intense interest, curiosity, or emotion; commanding attention; relating to or concerned in sensation;轰动 的； 耸人听闻的； 极好的； 绝妙的
3.whatsoever pron.无论什么； 任何
4.consumption n. the process of taking food into the body through the mouth (as by eating); involving the lungs with progressive wasting of the body; (economics) the utilization of economic goods to satisfy needs or in manufacturing; the act of consuming something 消费； 肺病； 耗尽； [医学]消耗性疾病

6. Thank you !