Questions & Answers about Moj pas uvijek trči kroz mračni tunel.
Why doesn't the ending of tunel change after the preposition kroz?
The preposition kroz always takes the accusative case to show movement through something. Because tunel is a masculine inanimate noun (a thing, not a living being), its accusative form is exactly the same as its dictionary (nominative) form.
I noticed the adjective is mračni instead of mračan. Why is that?
In the accusative case, adjectives describing masculine inanimate nouns keep their nominative form. We use the definite form mračni here because the English translation specifies 'the dark tunnel', referring to a specific known tunnel. If it were 'a dark tunnel', we would use the indefinite form mračan.
The word for dog is pas. What would happen to this word if it were the object of the sentence instead of the subject?
The noun pas is the subject here, so it is in the nominative case. If you wanted to say 'I see the dog', it would be the object in the accusative case. Because it is a living being, it changes form, and it also loses its middle letter due to a rule called the 'fleeting A', becoming psa.
Is the word order strict for adverbs like uvijek?
Adverbs of frequency like uvijek usually sit right before the verb they modify, which feels very natural to English speakers. You could place it at the very beginning of the sentence for extra emphasis, but the current word order is the most common and neutral choice.