The geometric shape of the work is derived from the image of a big tree. With the consideration of extending visual space, the work is presented as a trunk instead of a whole tree, and by doing so, the shadow extends the shape and connects to the function. Through resting under it, the work builds up a space embracing both the users and the ecological environment. After the work is installed, the appearance of the main trunk may change. Through long-term projects carried out by teachers and students, and with the activities held each year, the installation work completes in time. It will become a common memory of everyone in the school, a recollection that is worthy of pride and treasure.