Breakdown of Мы часто обсуждаем политику в социальных сетях.
мы
we
часто
often
в
in / to (direction)
политика
politics
Questions & Answers about Мы часто обсуждаем политику в социальных сетях.
Why does социальных end in -ых?
It is the prepositional plural form of the adjective социальный (social), matching the noun it describes. Adjectives in the prepositional plural take -ых after hard consonants, or -их after soft consonants and spelling-rule letters. Since н is a hard consonant, it takes -ых.
Why does the noun сетях end in -ях instead of -ах?
сетях is the prepositional plural of сеть (network). Nouns in the prepositional plural take -ах if they are hard, and -ях if they are soft. Because сеть is a feminine noun ending in a soft sign (-ь), it takes the soft ending -ях.
Why do we use the preposition в here when the English translation says "on"?
In English, we say "on" a network or "on" the internet. In Russian, you are considered to be "inside" them, so you use в (in) plus the prepositional case: в социальных сетях (on social networks) or в интернете (on the internet).
Why is the word for politics spelled политику here?
It is the direct object of the verb обсуждать (to discuss), so it must be in the accusative case. For feminine nouns ending in -а like политика, the ending changes to -у in the accusative case.