Questions & Answers about Девочка гуляет в парке.
Russian doesn’t use articles (words like a, an, the) at all.
The noun девочка can mean a girl or the girl, and парк / в парке can mean a park or the park.
Which one is meant (a/the) is understood from context, not from a special word:
- Девочка гуляет в парке. – could be “A girl is walking in the park” or “The girl is walking in the park.”
Гуляет is the 3rd person singular present tense form of the verb гулять (to walk / to stroll / to go for a walk).
The verb гулять is an -ать verb. In the present tense, its forms are:
- я гуляю – I walk / I am walking
- ты гуляешь – you walk (informal)
- он / она / оно гуляет – he / she / it walks
- мы гуляем – we walk
- вы гуляете – you walk (formal / plural)
- они гуляют – they walk
Because the subject is девочка (she), we use она гуляет → Девочка гуляет.