What are seven-character couplets?

The seven-character couplets are as follows: 1. Dragons and tigers leap across the human landscape, birds sing and flowers fragrance the heaven and earth in spring.

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2. The dragon and tiger leap into the new century, and it is a good time to be young and strong.

Horizontal comment: Tigers and tigers are powerful.

3. The dancing swallows and the singing songs are more beautiful than the flying dragons and the leaping tigers.

Horizontal comment: Tigers and tigers are powerful.

4. Soaring dragons and tigers leap across the bright land, and the sea, rivers and rivers are clear and beautiful.

Horizontal comment: Tigers and tigers are powerful.

5. The splendid future is full of dragons and tigers, and the glory is better than the dancing birds and singing songs.

Horizontal comment: Tigers and tigers are powerful.