【明報專訊】A POLITICAL PARTY has suggested that a tax be imposed on mainland visitors arriving by land to combat parallel trading and allay crowdedness in Hong Kong streets. It is aimed at tackling a problem Hong Kong is faced with, but it is neither advisable nor practicable to impose prohibitive taxes. Statistics show it is the multi-entry permit system that has caused Hong Kong problems of tourism, which will persist unless the government prescribes the right remedy - has the multi-entry permit system improved.