Dozing off while others speak is rude
Many young people in Hong Kong behave disrespectfully. They carry on chatting while teachers or public speakers are talking. Some even doze off.
That's just rude. It is a sign of respect to pay attention to people, even if you may not find what they are saying very interesting.
Imagine what it feels like to people to see that they are being ignored.
You surely do not like to be ignored, either, so make sure not to ignore others.
Mandy Tang Man-yin, Pooi To Middle School
In praise of online diaries
More and more people are writing daily blogs as a way of keeping a diary.
I believe writing a blog is an effective way for us to express our views and feelings. Rather than keep our emotions bottled up, we can pour our hearts out into our online diaries.
Some people may wonder why we make our feelings public instead of keeping them private in a traditional diary.
That's because through a blog we can share our views and feelings with our friends and relatives.
That also helps them keep track of what is going on in our lives. If they also write an online diary, we can follow their daily adventures, as well.
Emily Yu, Hang Seng School of Commerce
Exams have several benefits
Many students dislike exams, but I believe they are useful tools.
It is true that exams can put a lot of pressure on us. But they also enable us to learn to live with such pressure, which we will have to deal with as adults.
Exams are administered according to set rules. That, too, benefits students by helping them cope better in controlled environments.
Exams are useful for teachers who receive feedback about students' progress through the tests. Exams enable teachers to modify their teaching methods to make them more effective.
English teachers, for instance, can realise which parts of grammar most students find difficult and adjust their teaching accordingly.
In short, exams are hardly a waste of time.
Keith Cheng, Fung Kai Liu Man Shek Tong Secondary School
Green energy has its pros and cons
Many people are keen to adopt new and 'greener' energy sources. Yet renewable energy sources also have their drawbacks.
Although most renewable energy sources pollute less, they can still cause environmental problems.
Consider hydropower. New dams can wreak havoc with local ecosystems. Wind turbines cost a lot, which can make them a financial burden. So only rich countries can afford them.
Solar power, meanwhile, depends on the weather, which makes it an unsteady energy source.
While we should certainly seek to develop alternative energy sources, we also have to bear in mind their disadvantages.
One way to go about fixing our energy needs is to be less wasteful.
Diana Lam Hei-nok, St Antonius Girls' College
Tainted food is no laughing matter
There has been a series of food scandals on the mainland in the past few years. We have heard of a seemingly endless list of tainted products, from baby formulas to pork.
In fact, we have to question just how much food produced on the mainland is entirely safe.
Tainted products can be very harmful to our health. Melamine, an industrial chemical which has been used in milk products, can cause kidney failure. At least six children died and 300,000 others fell ill after drinking tainted milk powder.
Such manufacturers think only about profits. I understand that many of them may be having financial difficulties, but that is no excuse for endangering the lives of people.
On the bright side, the fact that we hear of such scandals in the first place is a good sign. That means Beijing is more open to criticism and ready to deal with problems.
Although problems remain, the central government has made a good start by trying to clamp down on such dangerous practices.
Ivory Chan Wing-gee, Leung Shek Chee College