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"Looking at the Sea" was written in September of the 12th year of Jian 'an (2007), when Cao Cao marched north to Wu Huan and wiped out Yuan Shao's remnants. This four-character poem depicts the magnificence of the motherland's rivers and mountains through the natural scenery that the poet saw when he climbed to the sea. It not only depicts the moving images of mountains and seas, but also expresses the heroic and optimistic enterprising spirit of the poet. It is a masterpiece describing natural scenery in Jian 'an period and one of the earliest representative works of China's classical landscape poems.