QUICKER clearance of Temporary Housing Areas (THA) will be given priority by Governor Chris Patten after he visited the oldest one in Hongkong yesterday. Ping Shek THA in Kwun Tong was built 18 years ago and now houses 1,700 people in units averaging 40 square feet per person. A noisy group of residents were ready to greet Mr Patten and his wife Lavender when they visited the home of the Cheung family. Mother-of-three Cheung Sau-lin, who represents the Ping Shek Concern Group and has lived there since it was built, wanted to give the Governor a piece of rotten wood from one of the houses as a symbol of their plight. She complained that her home was falling apart, had a leaky roof, and was infested with white ants, cockroaches and other insects. She said: ''Our hopes are high that he will do something after visiting us. ''We have asked the Housing Authority time and again to move us and to clean up and make the place better, but nothing has happened.'' Ping Shek will be demolished over the next three years, with half cleared before next April. Residents want the clearance to be done in one go. Before Ping Shek the Governor visited a Mutual Aid Committee at the nearby Shun On Estate and representatives from Shun Lee THA which lies in the middle, were upset that he had missed them out. Particularly disappointed was the Secretary of the Shun Lee Community Development Association, Cheng Tse-yau, who first challenged Mr Patten to visit the oldest THAs in a public question time last October. ''At least he has visited Ping Shek and knows some of our concerns,'' he said. ''Now it is time for him to seriously consider a comprehensive plan to resettle the tenants and eradicate these eyesores.'' Mr Patten said: ''In the last three years we have got rid of about 40 per cent of THAs. But unfortunately we have still got 50 schemes with about 65,000 people living in them. ''We are committed to reducing that by three-quarters by 1997, leaving 15,000 people living in THA accommodation by that time. ''Obviously we must keep that under review and if we can go faster and do better than that, then we must do so.''