Learn Hardcore Dutch: Onderweg naar de WC merk ik dat de cabine verrassend stil is. - On the way to the toilet I notice that the cabin is surprisingly quiet.

Onderweg is an adverb meaning “on the way” or “en route.” It indicates that you are in the process of traveling from one place to another. It is not a preposition—so you can’t take it as an object. You can put onderweg at the start of a sentence (front position) or after the verb (mid position).

Why does the sentence say Onderweg naar de WC merk ik… rather than Ik merk onderweg…?

Dutch main clauses follow the Verb‑Second (V2) rule: the conjugated verb must be in the second position. Since Onderweg occupies the first spot, merk moves to second and the subject ik comes after it. You could also say Ik merk onderweg naar de WC…, but then ik is in first position and merk in second.

Why is the verb is at the end of the clause dat de cabine verrassend stil is?

That clause is a subordinate clause introduced by dat (“that”). In Dutch subordinate clauses, the finite verb goes to the very end. That’s why is appears after stil instead of in the usual second spot.

Why doesn’t stil take an -e ending here? Shouldn’t it be stille?

Adjectives used predicatively (after a linking verb like zijn) stay in their base form. Since stil follows is, it remains stil. If you used it attributively—directly before a noun—you’d say de stille cabine or een stille cabine.

What does WC stand for, and how do you pronounce it in Dutch?

WC is an abbreviation of water closet (“toilet”). In Dutch it’s treated as a de‑word: de WC. Speakers pronounce the letters separately as “wé cé” (IPA /ʋeː seː/). You might also hear just toilet or the diminutive wc’tje.

What does cabine refer to in this context? Does it mean the same as an airplane cabin?

Here cabine means “stall” or “cubicle” in a public restroom—a small enclosed space. It doesn’t refer to an airplane cabin. In other contexts cabine can indeed mean “cabin,” but you rely on context to know which.

Is verrassend an adjective or an adverb? How does it work with stil?

In verrassend stil the word verrassend functions adverbially, modifying the adjective stil to mean “surprisingly quiet.” Dutch often uses participle forms like verrassend as adverbs without any change.

Could you rearrange the elements differently, for example Ik merk dat de cabine verrassend stil is onderweg naar de WC?

Yes, that is grammatically possible and simply shifts emphasis. Placing onderweg naar de WC at the end still yields a correct sentence:
• Ik merk dat de cabine verrassend stil is onderweg naar de WC.
Just remember that if you start with Onderweg naar de WC, you must invert subject and verb: Onderweg naar de WC merk ik….