Yet despite the benefits of operating landfills, the downsides are worth thinking about. The foul smell coming from landfills is one of the bad things about them.

Landfills also pollute the soil, and the chemicals in the waste can be harmful to health. I believe landfills are no longer a good option and the government should look at a bolder - but controversial - solution: building incinerators.

Former chief executive Tung Chee-hwa proposed this in 1999, but did not go further. Over the years, Shek Kwu Chau and Tuen Mun have been identified as good places to build incineration plants, which burn trash into ash and gas.

People are naturally worried that incinerator gases will contribute to global warming, but new technology has made the process clean and harmless.

Incinerators can even make electricity. In Macau and Germany, waste-burning plants can give enough power for 33,000 families.

In the end, building incinerators should be a priority or else Hong Kong will soon drown in garbage.

Sandy Mo, The YWCA Hioe Tjo Yoeng College

Teens should learn to spend wisely

Teenagers don't know how to manage their money. I think it's disturbing that they will buy things without thinking if they have enough to pay for the items.

Some of them spend 'future money', like buying things with credit cards.

They don't understand that they are piling up debt and that they have to pay for it someday.

Then teenagers get upset when they don't have enough money to repay the debt and ask their parents or teachers to help them.

Smart spending is common sense, so teens shouldn't blame their parents for not teaching them how to manage their money. Organisations that give teens loans should also know better.

Spending only what you can afford is something that every person should know. Debt has serious effects and reckless teens should be ready to face the punishment.

Wong Chi-fa, Fanling Rhenish Church Secondary School

Good deed by helper made my day

Nowadays in Hong Kong, there are many helpers who come from the Philippines or Indonesia. Usually their employers don't treat them nicely.

But even if these foreign workers don't get treated the way they should, they are still nice to other people - even Hongkongers who are not their bosses.

I was on my way home one day and a helper said something to me. At first, I didn't know what she said because her Cantonese was not good. She said it again slowly so that I could understand. And finally I got her message: I had dropped my wallet on the street.

This surprising good deed taught me to always be kind to others because they will be kind to you.

Lindy Pang In-yin, STFA Tam Pak Yu College

Stress can cause sleepless nights

I am writing to talk about a problem for many Hongkongers: insomnia, which is when a person finds it hard to fall asleep.

While it is common among older people, teenagers can get insomnia, too. I can think of many reasons why teens can't sleep.

They have a lot more homework nowadays, along with extra-curricular and other activities. The pressure to do better than other students also causes them to worry so much that they lose sleep.

Also, some teens have 'monster parents' who force them to learn as much as possible at a very young age. Children might be scared that they cannot meet the high standards of their parents and teachers. As a result, they study until midnight, and miss out on much-needed sleep.

I think we should start asking more questions on why more young people have insomnia. The government, for example, should look at ways to make living in the city less stressful.

Ng Suet-man, The Chinese Foundation Secondary School