In ancient China, the study room of intellectuals (文人) was called wen fang in Chinese. Because the writing brush, ink, paper and inkstone（ 砚 台 ） are used in the study room. They are called the "Four (Treasure) of the Study" or wen fang si bao in Chinese.
The writing brush is a special writing and painting tool in ancient
China. Brushes are (usual) made of animal hair. Rabbit hair was the (one) to be used. According to record, the ancient Chinese also used human hair (make) brushes.
Ink is a black material used in calligraphy (书法) and painting. It was born (late) than the writing brush. After the Han and Wei Dynasties, ink-making technology became more and more developed, and Huizhou became the(nation) ink-making center in the Ming Dynasty. The "Hui Ink" produced there is famous all over the world.
Papermaking (invent) in the Western Han Dynasty and improved by Cai Lun during the Eastern Han Dynasty. After the Song Dynasty, more and more types of paper appeared. The most famous one is Xuan paper. Xuan paper is thin but tough, and (not change) color easily. So, it's (know) as the "thousand-year-old paper".
The ink stone is generally made of stones. In the Qing Dynasty, people carved (雕刻) some patterns on it. Since then, the inkstone has not only been practical, but also had the (valuable) of collection and appreciation.
