Learn Hardcore Dutch: Wij wachten bij de receptie tot de vergadering begint. - We wait at the reception until the meeting begins.

The preposition bij indicates a location at or by something. In contrast, op means on top of, which doesn’t fit for standing beside a desk, and aan is used for things attached to or alongside surfaces (e.g. aan de muur, aan de telefoon). Therefore bij de receptie means at the reception desk. You could also say aan de balie (at the counter), but bij is more general.

Why is there a definite article de before receptie? Could we say we wachten bij receptie?

In Dutch, most singular countable nouns need an article (definite de or indefinite een). Omitting the article (we wachten bij receptie) sounds ungrammatical. You could use een if you mean a reception (like a party): bij een receptie, but for the place in a building you use de receptie.

Can we drop wij and just say wachten bij de receptie tot de vergadering begint?

In the indicative mood, Dutch requires a subject, so you need wij or its informal variant we. The difference is that we is more colloquial. With wij, the sentence feels more formal or emphatic. So you write We wachten or Wij wachten, but you can’t omit the subject completely.

Why is tot used here, and what about totdat?

Both tot and totdat introduce subordinate clauses meaning until. totdat is slightly more formal and explicitly flags a clause, but tot works the same way: it’s a subordinating conjunction that sends the verb to the end of the clause. Compare:

We wachten bij de receptie tot de vergadering begint.
We wachten bij de receptie totdat de vergadering begint.
In everyday speech, tot is very common.

Why does the verb begint appear at the end in tot de vergadering begint instead of in second position?

Because clauses introduced by subordinating conjunctions (like tot or omdat) use verb-final word order. That means the finite verb comes last. Here tot marks the start of the subordinate clause, then the subject de vergadering, then the verb begint.

What’s the difference between wachten op and wachten tot?

wachten op + noun/pronoun = to wait for someone or something (Ik wacht op de bus.)
wachten tot + clause = to wait until an event happens (Ik wacht tot de bus komt.)
You use op for concrete objects or persons; you use tot/totdat when you’re waiting for an action or a point in time described by a clause.

Why is vergadering preceded by de? How do you know its gender?

vergadering is a common-gender noun, so it takes de (all singular common-gender nouns use de; neuter ones use het). There’s no foolproof rule, but many nouns ending in -ing are common gender. Over time you learn which words take de and which take het.

Why is beginnen conjugated as begint here?

The present-tense conjugation of beginnen is:

ik begin
jij begint
hij/zij/het begint
wij/jullie/zij beginnen
Since de vergadering is third-person singular, you use begint.

Does receptie refer to the act of receiving, the desk, or the person?

Here receptie means the reception desk or area in a building (where visitors check in). It does not refer to the person; a receptionist is receptionist in Dutch. Nor is it a party (another meaning of receptie), because that would usually be een receptie geven (“to give a reception”).