Mask is a must ! Wearing a mask protects you against coronavirus. The main concept of the poster is using two capital M to create the shape of the mask. The exclamation mark shows how important this action is and warn the public. Mask is a must！ 戴口罩可以预防冠状病毒的散播。 海报的主要概念是使用Mask和Must两个大写字母M来创造出口罩的形状。 整體造型成一個感叹号，用以警示世人戴口罩的重要性。