In academic, formal, and scientific Russian, you will frequently encounter present passive participles. They act as adjectives and describe a noun that is currently having an action done to it (e.g., "the studied process" or "the method being applied").
Forming Participles and Adding the "Doer"
To form a present passive participle, start with an imperfective verb and look at its present-tense "we" form (e.g., изучать -> мы изучаем). Then, simply attach the standard adjective endings (-ый, -ая, -ое, -ые).
If you want to specify who is performing the action—equivalent to "by someone" in English—put that noun in the Instrumental case.
| This term describes a process studied by scientists. | Этот термин описывает процесс, изучаемый учёными. |
Agreement and Declension
Because these participles function exactly like adjectives, they must agree with the noun they modify in gender, number, and case.
| The discussed theory describes modern society. | Обсуждаемая теория описывает современное общество. |
| The applied method explains this phenomenon. | Применяемый метод объясняет это явление. |
When the grammatical role of the noun changes, the participle declines just like a regular adjective (such as новый). Here it is in the Genitive case:
| This concept is an important part of the applied method. | Это понятие — важная часть применяемого метода. |
And here it is in the Accusative case (which matches the Nominative for inanimate nouns):
| We do not understand the discussed term. | Мы не понимаем обсуждаемый термин. |
Participles Ending in -им- and -ом-
The participle's core vowel depends on the verb's conjugation. First conjugation verbs use -ем-, as seen in the examples above.
Second conjugation verbs use -им-, which naturally comes from their "we" form (e.g., видеть -> мы видим -> видимый).
| The visible part of the planet is very beautiful. | Видимая часть планеты очень красивая. |
Finally, a few older or irregular verbs take the suffix -ом-. A very common example in theoretical and academic texts is искомый ("sought" or "being searched for", derived from искать).
| The concept being described is the sought element of the theory. | Описываемое понятие — это искомый элемент теории. |