Breakdown of Waarom wacht de bus nog bij de halte?
wachten
to wait
de bus
the bus
waarom
why
bij
at / near / by
Questions & Answers about Waarom wacht de bus nog bij de halte?
How does nog change the meaning of this sentence?
Without nog, the sentence is just Waarom wacht de bus bij de halte? (Why is the bus waiting at the stop?). Adding nog adds the meaning of "still". It emphasizes that the waiting started in the past and is continuing into the present, which fits right into this lesson's focus on time contrast.
Where exactly should time particles like nog, al, or pas go in a question like this?
In a question starting with a question word (Waarom), the verb (wacht) comes second, followed by the subject (de bus). Short time adverbs like nog usually go immediately after the subject, and before prepositional phrases indicating place, like bij de halte.
The English translation says "is waiting". Why doesn't the Dutch sentence use the continuous form aan het wachten?
You absolutely could say Waarom is de bus nog aan het wachten, but it is not necessary. In Dutch, the simple present (wacht) is used much more often than in English for things happening right now. Because the word nog (still) already makes it obvious that the action is ongoing, the simple present sounds perfectly natural.
Why do we use the preposition bij here instead of op for "at the stop"?