In written Russian, a participial phrase (причастный оборот) consists of a participle and its dependent words. Punctuation depends entirely on where the phrase sits in relation to the noun it modifies.
After the Noun (Commas Required)
When a participial phrase comes after the noun it modifies, it must be set off by commas. If the sentence continues after the phrase, use commas on both sides to isolate it.
| The scroll found in the archive is an original. | Свиток, найденный в архиве, является оригиналом. |
Notice how найденный в архиве (found in the archive) describes the noun свиток (scroll). Because it follows the noun, it is enclosed in commas.
| The quill, chosen by the copyist, is ideal for calligraphy. | Перо, выбранное переписчиком, идеально для каллиграфии. |
Before the Noun (No Commas)
If you place the participial phrase before the noun it modifies, the commas disappear.
| The copyist used a quill made by the monk. | Переписчик использовал сделанное монахом перо. |
Here, the phrase сделанное монахом (made by the monk) directly precedes the noun перо (quill), so no punctuation is needed to separate them.
| The strokes written in ink are amazing. | Написанные чернилами штрихи удивительны. |
Keeping the Phrase Intact
There is one strict word order rule: a participial phrase cannot be broken up by the noun it describes. The modified noun must sit entirely outside the phrase—either right before its first word, or right after its last word.
| A stroke added by the master completely changes the capital letter. | Добавленный мастером штрих полностью меняет заглавную букву. |
The noun штрих (stroke) sits safely after the unbroken phrase добавленный мастером (added by the master).
| The capital letters, decorated with an ornament, are written in red-colored ink. | Заглавные буквы, украшенные орнаментом, написаны чернилами красного цвета. |