Questions & Answers about Nu de luier vies is, verschoon ik de baby.
Why is the verb is at the very end of the first clause?
In this sentence, nu acts as a subordinating conjunction meaning "now that". Just like with words like omdat (because) or hoewel (although), it pushes the conjugated verb (is) to the very end of its clause.
How does the grammar tell us that nu means "now that" instead of just "now"?
The word order is your biggest clue. If nu just meant "now", it would act as a regular time adverb in the first position, causing the verb to come second: Nu is de luier vies (Now the diaper is dirty). Because the verb is gets pushed to the end instead, we know nu is acting as a conjunction meaning "now that".
Why is it verschoon ik and not ik verschoon after the comma?
The English translation says "changing", so why not use the verb veranderen?
The verb veranderen means to change in the sense of altering, modifying, or transforming something. Verschonen contains the word schoon (clean) and is used specifically for changing a baby's diaper, putting on fresh clothes, or putting clean sheets on a bed.