The extension need to be closely connected to the old library at the edge of hillside with a height difference larger than10m. The upper part is lifted up, while the bottom sinks beneath the ground. Two floors in the middle are almost opened to outside where stairs and ramps are organized as an interesting walk way connecting the dinning hall and the teaching building. The level height, façade proportion and scale of the new built part are derived from the original part. Vertical sun-shades of the facades made the building looks lighter and softened the sunlight in the reading room.