Nowadays， more and more people are using mobile phones. In the street， on a bus， in a restaurant， actually in every other public places， you can hear someone speaking with a mobile phone. Many college students have bought mobile phones， too.
The mobile phone is so popular because of many reasons. First of all， it is a very useful communication tool. When you are out and you need to contact someone urgently， a mobile phone will enable you to do this if there is no telephone box nearby. A beeper is not always sufficient for your purposes. Second， it is a fashionable product which many youths want to have. Mobile phone manufacturers have used famous stars as their propagandists. At last， the prices of mobile phones are dropping as a result of the scientific development. Ordinary people can afford a mobile phone now. The mobile phone is getting more and more accepted by the common public.
However， the mobile phone can also become a nuisance sometimes. In a classroom when everybody is taking an important exam， the ring of a mobile phone causes almost some kind of sound pollution. Those who have mobile phones should avoid disturbing others in public places.