Use these words and phrases to help you on any business/finance writing questions!
If you look at the picture, you will see that there is excess demand (求過於供) for homework assignment since the P (price 價格) = 0.
In this graph, the demand for homework 需求量 (QD) = 14, but the supply of homework 供應量 (QS) = 2。
因此，當價格 = 0 時，需求量 > 供應量 ，這情況稱為「超額需求 (excess demand)」。這即是我們日常所說的供不應求。
Source and more basic econ info: