Learn Hardcore Russian: Моя подруга светится, потому что она счастлива.

Светится comes from the verb светить with the reflexive ending -ся. In this sentence, it means “to glow” or “to radiate.” Rather than suggesting a literal glow, it figuratively describes how her happiness makes her appear radiant.

Why is the verb written with the -ся ending?

The -ся ending makes the verb reflexive. In this context, it indicates that the subject is experiencing or displaying a state internally—as if her inner happiness causes her to glow. This reflexive form is common in Russian for expressing inherent states or conditions without implying a deliberate action.

Why is there a comma before потому что?

In Russian, subordinate clauses introduced by conjunctions like потому что (meaning “because”) are separated from the main clause by a comma. Here, the subordinate clause потому что она счастлива explains the reason why the main clause Моя подруга светится is true.

How do the adjectives моя and счастлива agree with the noun подруга?

Both adjectives are in the feminine singular form to match the noun подруга, which is feminine. Моя is a possessive adjective in the nominative case, and счастлива is a short-form predicate adjective describing her state. Their forms ensure that they agree in gender and number with подруга.

What is the overall sentence structure here?

The sentence is composed of two parts: a main clause and a subordinate clause. The main clause Моя подруга светится states the observation, while the subordinate clause потому что она счастлива gives the reason behind it. This cause-and-effect structure is typical in Russian, where a comma marks the beginning of the explanatory clause.

Why is there no explicit verb like “is” before счастлива?

In Russian, the present tense of the linking verb быть (“to be”) is usually omitted. That’s why она счастлива directly translates to “she is happy.” The adjective счастлива functions as the predicate without needing an additional verb to convey the state.