Learn Hardcore German: Die Teamleiterin bleibt ruhig, obwohl der Termin verschoben wird. - The team leader remains calm, although the appointment is being postponed.

In German, obwohl is a subordinating conjunction (like weil, dass, wenn, etc.).
In clauses introduced by such conjunctions, the conjugated verb goes to the end of the clause.

Main clause: Der Termin wird verschoben. – normal verb-second word order.
Subordinate clause: obwohl der Termin verschoben wird – verb (wird) moves to the end.

So obwohl der Termin verschoben wird literally has the structure:
although the appointment postponed is.

Can I start the sentence with the obwohl-clause?

Yes. You can put the subordinate clause first:

Obwohl der Termin verschoben wird, bleibt die Teamleiterin ruhig.

Two things to note:

You still need a comma between the clauses.
When the subordinate clause comes first, the following main clause still has verb-second word order, so you get:
- bleibt die Teamleiterin ruhig (verb bleibt in second position).

What exactly does obwohl mean here, and how is it different from trotzdem?

obwohl introduces a concessive subordinate clause: it means although / even though.

Die Teamleiterin bleibt ruhig, obwohl der Termin verschoben wird.
→ She stays calm, *although the appointment is being postponed.*

trotzdem is an adverb, not a conjunction. It roughly means nevertheless / in spite of that and starts a new main clause:

Der Termin wird verschoben. Trotzdem bleibt die Teamleiterin ruhig.
→ The appointment is being postponed. *Nevertheless, the team leader stays calm.*

So:

obwohl = connects two clauses in one sentence, verb of the subordinate clause goes to the end.
trotzdem = separate main clause, normal verb-second position after trotzdem:
Trotzdem bleibt die Teamleiterin ruhig.

Why is there a comma before obwohl?

German always separates a main clause and a subordinate clause with a comma.

Die Teamleiterin bleibt ruhig, obwohl der Termin verschoben wird.
Obwohl der Termin verschoben wird, bleibt die Teamleiterin ruhig.

It doesn’t matter whether the subordinate clause comes first or second – the comma is obligatory in both cases.

Why is it der Termin and not den Termin in obwohl der Termin verschoben wird?

Because this is a passive construction, and in the passive the former direct object becomes the subject in nominative.

Active:
Jemand verschiebt den Termin.
– den Termin = accusative object.
Passive:
Der Termin wird verschoben.
– der Termin = nominative subject.

In obwohl der Termin verschoben wird, der Termin is the subject of the passive verb phrase wird verschoben. That’s why it’s der (nominative) and not den (accusative).

What tense and voice is wird verschoben, and why not ist verschoben?

wird verschoben is present tense passive (called Vorgangspassiv – event passive):

Der Termin wird verschoben.
→ The appointment is being postponed / is (getting) postponed.

It focuses on the action of postponing.

ist verschoben is state passive (Zustandspassiv) with sein + Partizip II:

Der Termin ist verschoben.
→ The appointment is postponed / has been postponed (and is now in that state).

It focuses on the resulting state after the action has already happened.

In obwohl der Termin verschoben wird, the idea is that the postponement is taking place / is happening (or has just been decided), so the event passive wird verschoben is appropriate.

What would the active version of der Termin wird verschoben look like?

The corresponding active sentence would be:

Jemand verschiebt den Termin. – Someone is postponing the appointment.
Or more concretely: Der Chef verschiebt den Termin. – The boss is postponing the appointment.

So you can see the transformation:

Aktiv: Der Chef verschiebt den Termin.
Passiv: Der Termin wird (vom Chef) verschoben.

Why is it bleibt ruhig and not ist ruhig?

Both are grammatically correct, but they have different nuances:

ist ruhig = is calm – describes a state.
bleibt ruhig = stays/remains calm – emphasizes that the person does not stop being calm, even though something might make others nervous.

In this context, bleibt ruhig fits better, because the obwohl-clause introduces something potentially stressful (the appointment is being postponed). The sentence highlights that she keeps her calm instead of getting upset.

Why is Die capitalized in Die Teamleiterin? Is it always capitalized?

Here Die is capitalized only because it is the first word of the sentence.

In normal sentence position, the article is lowercase:

die Teamleiterin bleibt ruhig (in the middle of a sentence).

What is always capitalized is the noun Teamleiterin, because all nouns are capitalized in German. So:

At sentence start: Die Teamleiterin bleibt ruhig.
In the middle: Ich finde, dass die Teamleiterin ruhig bleibt.

How do we know Teamleiterin is feminine, and what is the masculine form?

The ending -in marks a female person in many profession and role nouns in German.

Teamleiter = male team leader (masculine).
Teamleiterin = female team leader (feminine).

Accordingly, the articles change:

der Teamleiter – the (male) team leader.
die Teamleiterin – the (female) team leader.

So Die Teamleiterin bleibt ruhig ... clearly tells you that the team leader is female.

Could I say obwohl der Termin verschoben sein wird to express “although the appointment will be postponed”?

You can say obwohl der Termin verschoben sein wird, but it is unusual and heavy in everyday German.

German mostly uses the present tense to talk about the (near) future when the context is clear:

Obwohl der Termin verschoben wird, bleibt die Teamleiterin ruhig.
→ contextually: Although the appointment is going to be postponed, she stays calm.

You only really need Futur (with werden) when there is a risk of misunderstanding or when you want to stress the future aspect strongly. In most cases, the simple present wird verschoben is the natural choice.