fern
Ferns (Polypodiopsida or Polypodiophyta) are a group of flowerless and seedless plants. They do not have fronds and roots, and reproduce via spores. Their foliage formation is triangular.
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蕨类植物（Polypodiopsida 或 Polypodiophyta）是一类无花无籽植物。它们没有叶和根，通过孢子繁殖。它们的叶子形状是三角形的。