Questions & Answers about Tipkajući, pio je kavu s mlijekom.
How exactly do we build the word tipkajući?
It is the present verbal adverb of the verb tipkati (to type). To form it, you take the 'they' form of the present tense, which is tipkaju (they type), and simply add -ći to the end.
Why use tipkajući instead of saying dok je tipkao (while he was typing)?
Both are correct, but using the -ći ending is a very elegant way to show that two actions are happening simultaneously and are done by the exact same subject. It means he was typing at the exact same moment he was drinking his coffee.
If tipkajući is a present verbal adverb, why is the rest of the sentence in the past tense (pio je)?
The 'present' in the name just means the action happens at the same time as the main verb, not that it has to happen right now in the present tense. Because the main verb pio je is in the past tense, we know the typing also happened in the past.
Why does mlijeko change to mlijekom here?
The preposition s (with) requires the instrumental case when it shows accompaniment or addition, like adding milk to coffee. For the neuter noun mlijeko, the instrumental ending is -om, making it s mlijekom.