Like the cheongsam, the upheavals of the twentieth century made the ao dai unfashionable for long periods. This was  particularly true in the seventies, as austerity drives caused the Vietnamese to shelve the ao dai as an impractical  luxury. It was only with the brightening economy of the late eighties and the early nineties that the ao dai made its  comeback and today, the dress is a common sight on Vietnamese streets. It is the standard uniform of schoolgirls. It can  be seen on office women going about their daily tasks. Tailor step out in ao dais. Traditionally, the colour of the ao dai indicated age: pure white for girls, soft pastel colours for young, marriageable woman and strong, rich colours for the older ladies. Although the traditional robe-and-vest has virtually disappeared, the comfortable Tang suit has survived, and  remains a formal wear choice for a select few. Originally, the Tang suit was a term foreigners used, in a sweeping way, to describe all Chinese fashion. In fact, what people have over time come to define as the Tang suit is something that was created in the late  Qing and early Republican era among the common people.  It is cut wide, with long sleeves, buttons in the front, and a stiff collar. The lines are simple and generous. There is no class restriction on the Tang suit; its enthusiasts can be found in commerce, government, and academia. Examples include the scholar Wang Chien-hua, the ethnomusicologist Lin Ku-fang, and the well-known businessmen Huang Jen-chung and Wong Ta-ming.  They find pleasure in wearing Tang suits for classes, meetings, and all kinds of formal affairs. Wang Chen-hua began wearing Tang suits 20 years ago. He says that the Tang suit is comfortable and easy to move around in. Moreover, unlike a Western suit, it is not open in the front and so keeps out the cold better. Moreover, the Tang suit has "personality." It displays an individual's character and aesthetic.  Yu Yuh-chao has "suffered a blow" at a number of international conferences. He is determined to reshape the  image Chinese project, and to encourage culture in daily life. Yu, who worked in the Ministry of Education  for many years, is strongly promoting the creation of a new national attire. He notes that modern national  dress must have five key characteristics: it must be comfortable, artistic, modern, suited to the locality,  and universal. He calls his ideal national dress shuya, which means "comfortable and elegant." Taking the  lead himself, two years ago he put aside his Western suits and asked a tailor to make a shuya outfit that  Yu himself had designed. He wears it to work and to give lectures.  So what is shuya clothing, that it doesn't lose the spirit of traditional Chinese culture yet conforms to  the needs of modern life? This March, the Council for Cultural Affairs and Fujen Catholic University, aiming to promote innovation  in national costume design, co-sponsored an academic conference and a design competition on the theme of  "Comfortable and Elegant Dress Suited to Taiwan's Local Conditions."