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Yesterday again / Calendar

Yesterday again
Yesterday again

Calendars have been widely used in China. When a day is past, people will tear the page from the calendar. Usually calendar papers are thrown into the trash, which causes great waste of resources.
The pages of calendar are made of biodegradable plastic, which can be used as a trash bag for secondary use.We can use the yesterday page of calendar to take more rubbish.
The date on the trash bag reminds us that trash cannot be preserved till the third day. Therefore we should replace trash bag in time that help us keep the environment clean.


Northwestern Polytechnical

Northwestern Polytechnical
University Ming De College
xi‘an, China



Nantong,China, China

Shixiao Li Chao Ren Dan Gao Diguan Feng