First of all, the quoted sentences should conform to the theme and intention of the poem and the poet's creative thought. If the quoted sentences are inconsistent with the theme and intention of the poem, it will produce a sense of disharmony and affect the quality of the whole poem.
Secondly, the quoted sentences should be properly processed and transformed to conform to the form and rhythm of poetry. Poetry is a highly concise and formalized literary genre, and every word and sentence has a specific position and function. If the quoted sentences are not in harmony with the form and rhythm of the poem, it will destroy the harmonious beauty of the whole poem.
Thirdly, the quoted sentences should conform to the background and cultural tradition of poetry. Poetry is the product of culture, and poetry in different times and cultural backgrounds has different styles and characteristics. If the quoted sentence is inconsistent with the background and cultural tradition of the poem, it will have an unreal feeling and affect the quality of the whole poem.
In a word, quoting other people's sentences in poetry creation needs careful consideration, proper processing and transformation, which conforms to the theme, form, background and cultural tradition of poetry, so as to achieve perfect artistic effect.