Learn Russian: Это восточный парк.

In Russian, the present tense of the verb 'to be' (like 'am', 'is', or 'are') is generally skipped. So, Это восточный парк literally translates to 'This eastern park,' which we naturally understand as 'This is an eastern park.'

Since парк is a masculine word, why does Это end in -о?

When Это is used to mean 'this is' to introduce a new subject, it acts as a fixed pointing word and never changes its spelling. It stays exactly the same (Это) regardless of the gender of the noun. You would only use the masculine form Этот if you wanted to say 'this park' without the 'is' (for example, Этот парк восточный meaning 'This park is eastern').

Why does the adjective восточный end in -ый?

Adjectives in Russian must change their endings to match the gender of the noun they describe. Since парк is a masculine noun (we know this because it ends in a consonant), the adjective takes the standard masculine dictionary ending -ый.

Where are the words for 'a' or 'an' in the Russian sentence?

Russian does not have articles like 'a', 'an', or 'the'. Depending on the context, парк can mean 'park', 'a park', or 'the park'. Here, the English translation adds 'an' so the sentence sounds grammatically correct to English speakers.