Learn Polish: Zanim obudziłem dziecko, cichutko i wolniutko zamknąłem drzwi. - Before I woke up the child, I closed the door very quietly and very slowly.

They are diminutive forms of the standard adverbs cicho (quietly) and wolno (slowly). In Polish, adding diminutive suffixes like -utko or -iutko to adverbs usually intensifies them (meaning "very quietly" or "very slowly") while adding a sense of gentleness, care, or affection. Here, it emphasizes how delicately the speaker acted to avoid waking the child.

Why is there an extra "i" in wolniutko compared to cichutko?

The base suffix used here is -utko. When attaching it to the stem of wolno (woln-), the n softens to a ń sound, which is spelled as ni before the vowel u (giving us wolniutko). The stem of cicho ends in ch, which takes the -utko suffix directly without needing that softening vowel.

Why are both verbs, obudziłem and zamknąłem, in the perfective aspect here?

The sentence describes completed actions in a sequence. Using the perfective obudziłem after zanim (before) indicates that waking the child was a distinct, completed event that the speaker wanted to preempt. If you used the imperfective budziłem, it would mean "before I was in the process of waking up the child," which sounds unnatural here.