News at Eleven: Within the shi and ci genres,

there were different names for the various types and structures of poems. The jin ti shi (recent form), which Li Bai and Du Fu were particularly skillful in mastering, was the strictest in terms of rules.

The most common form was the five- and seven-character poem, both of which were required to end in four or eight lines. The four-lined poem is called a jue shi, while the eight-lined poem is a lu shi.

from The Epoch Times: Staten Island Reads Chinese Poetry

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