By comparison, driving on the roads does not require any great skills; what it does require is concentration, patience and attention to detail. If bus drivers can meet these criteria and give me a comfortable ride, I will thank them every time.

North Korea has undermined its relations with other countries with its latest threat of a "pre-emptive nuclear strike against the United States" ("Pyongyang threatens nuclear strike", March 8).

Its leadership has traditionally presented a negative image on the world stage, with the emphasis always on military development and becoming a nuclear power.

This concentration on military might ignores other aspects that should matter to the nation, for example, economic development and the importance of diplomacy.

Given the size of its army it should not have security concerns, but even its strongest allies have expressed a reluctance to co-operate with it as a result of its latest nuclear threat against Washington.

As North Korea alienates itself from more countries on the world stage, this can only lead to greater instability and it makes it more difficult to arrive at a diplomatic solution to existing problems.

There has to be a change of attitude on the part of the leaders in Pyongyang.

They have to recognise the importance of winning the trust of other countries and co-operating with them, rather than concentrating on a rapid build-up of military power.

They must recognise the importance of trying to accelerate economic development in their country, thereby improving the living standards of North Korea's citizens.

North Korea is far behind many countries, including developing nations, in this regard.

It should be seeking to adopt an open-door policy so that its economy can move forward rather than creating a military crisis, which places it on a state of alert.

As most readers will be aware, the Hong Kong government has imposed a quite harsh milk powder export restriction.

I think it is an effective way to curb the problem of smuggling [and parallel trading] to the mainland.

However, although it clearly has support from the mainstream of society, some legislative councillors are concerned that it will harm Hong Kong's image as a free-trade city and they want the administration to implement a sunset clause. I understand their concerns, but do not think this is necessary.

The reason so many mainlanders want to purchase milk formula here is because of food safety scandals over the border, especially relating to melamine in milk powder. Therefore, they prefer milk powder sold in Hong Kong which has been directly imported from Europe.

I hope food safety standards will improve on the mainland, but it will take a few years. If we impose a sunset clause then the smugglers will return. For this reason, it would not be appropriate to have a sunset clause at this time.

However, the government could set a date when it will review the policy and its effectiveness.

I refer to the report ("Beware of traps, Xi tells officials", March 10).

Communist Party chief Xi Jinping said, "There are many temptations in society today and too many traps awaiting officials with special powers."

However, the problem is that the central government has enormous power and regulations do not exist which place controls on officials who get involved in the business sector on the mainland.

To get ahead, people need to have money and good relations with officials. Having a good relationship is essential if you want your company's products to be sold. Foreign investors who want to enter the mainland market are aware this is how things operate.

Western investors may often set up a branch office in Hong Kong first, before establishing themselves on the mainland.

Here, they enjoy the benefits of an economic system that adheres to the rule of law. Various agencies exist to ensure that the law is obeyed, such as the Independent Commission Against Corruption. It is clear that these investors do not have the same faith in the rule of law north of the border.

History has shown that it takes time to get rid of bad habits. However, the central government should recognise that there is a problem and it should try and deal with it.

Some observers have claimed that China could overtake America in less than a decade.

I can see this happening in some respects - for example, it could become the world's largest economy. But I do not see it surpassing the US in political and social terms. America has an established system of law and order.

This is something China also needs to do if it is to become a great nation.

The old habits will have to change if it wants to move forward.

I have the great privilege to enjoy a morning jog on the south side of Hong Kong Island, along the promenade, enjoying the morning breeze and the sea view.

But what I experienced last Thursday morning was not a privilege, rather the opposite. Shame on those people who were at the barbecue site in Deep Water Bay on Wednesday night.

At 6.30am the whole area near the pristine beach was full of smashed beer and vodka bottles, leftover food and a massive amount of foul-smelling litter. They had not even bothered to use the litter bins which were empty. This kind of irresponsible behaviour is totally unacceptable, wherever it may be, and the perpetrators should be punished.

I felt sorry for the cleaners who were entering the site as I passed, having to clean up after these polluters.