Learn Dutch: Gaan jullie op kantoor samenwerken? - Are you going to work together in the office?

This is the standard word order for the future tense using gaan. The auxiliary verb (gaan) takes the normal verb position next to the subject, and it pushes the main action verb (samenwerken) in its full dictionary form to the very end of the sentence.

Why is it op kantoor instead of in kantoor for "in the office"?

In Dutch, op (literally "on") is often used for locations tied to an activity, like work or school. Op kantoor is a fixed phrase that translates to "at the office" or "in the office". Notice that we also drop the word "the" (het) in this phrase.

Is samenwerken a separable verb?

Yes, it is made of samen (together) and werken (to work). However, because the future tense rule pushes the entire infinitive to the end of the sentence, it stays connected as a single word here. If you used it in the present tense without gaan, it would split: Jullie werken op kantoor samen.

Why does gaan come before jullie?

Because this is a yes/no question. To turn a statement (Jullie gaan) into a question, you swap the subject and the conjugated verb. So, gaan moves to the very front.