Learn Hardcore German: Der Notarzt kommt schnell, damit der Patient nicht lange warten muss. - The emergency doctor comes quickly so that the patient does not have to wait long.

In German, damit introduces a subordinate clause (a dependent clause). Subordinate clauses are normally separated from the main clause by a comma.

Main clause: Der Notarzt kommt schnell,
Subordinate clause: damit der Patient nicht lange warten muss.

So the comma marks the beginning of the subordinate clause introduced by damit.

What exactly does damit mean here, and how is it different from dass or um … zu?

In this sentence, damit means “so that / in order that” and introduces a purpose:

Der Notarzt kommt schnell, damit der Patient nicht lange warten muss.
→ The emergency doctor comes quickly so that the patient doesn’t have to wait long.

Differences:

damit vs dass
- damit = purpose / intention
  - Ich rufe den Notarzt, damit er schnell kommt.
    (I call the emergency doctor so that he comes quickly.)
- dass = content / fact (“that”)
  - Ich weiß, dass der Notarzt schnell kommt.
    (I know that the emergency doctor comes quickly.)
damit vs um … zu
- um … zu is also purpose, but used when the subject is the same in both clauses:
  - Ich rufe den Notarzt, um Hilfe zu bekommen.
    (I call the emergency doctor in order to get help.)
- damit is used when the subjects are different:
  - Ich rufe den Notarzt, damit der Patient Hilfe bekommt.
    (I call the emergency doctor so that the patient gets help.)

In your sentence, the subjects are different (der Notarzt / der Patient), so damit is the correct choice.

Why is the verb at the end in damit der Patient nicht lange warten muss?

Because damit introduces a subordinate clause. In German subordinate clauses, the conjugated verb goes to the end of the clause.

Main clause word order: Der Notarzt kommt schnell.
(Verb in 2nd position: kommt)
Subordinate clause word order: damit der Patient nicht lange warten muss.
(Conjugated verb muss is at the end.)

So the pattern is:

[damit] + [subject] + (other elements) + [verb at the end]
→ damit der Patient nicht lange warten muss

Why is the order warten muss and not muss warten?

In subordinate clauses with a modal verb (like müssen) and a main verb (like warten), both verbs go to the end, and the modal verb comes last:

… damit der Patient nicht lange warten muss.

General pattern in subordinate clauses:

… weil er gehen muss. (must go)
… obwohl sie arbeiten will. (wants to work)
… dass wir kommen können. (can come)

So warten muss is required;
✗ damit der Patient nicht lange muss warten is wrong in standard German.

Why is it muss and not müssen?

The verb must agree with the subject:

Subject: der Patient → 3rd person singular
Verb: müssen → 3rd person singular = muss

Some forms of müssen:

ich muss
du musst
er/sie/es muss
wir müssen
ihr müsst
sie/Sie müssen

Because der Patient is singular, the correct form is muss.

Why is it der Patient and not den Patienten?

Here, der Patient is the subject of the subordinate clause; the subject is in the nominative case.

der Patient (nominative singular, masculine) = the one who does the action of warten muss.

You would use den Patienten (accusative) if he were a direct object, for example:

Der Notarzt untersucht den Patienten.
(The emergency doctor examines the patient.)

In your sentence, the patient is not an object; he is the one who must (not) wait, so der Patient is correct.

Why is the sentence in the present tense (kommt) although it’s about the future?

In German, the present tense is often used to talk about the near future, especially when the context makes it clear:

Der Notarzt kommt schnell.
→ He is coming quickly / will come quickly.

Compare:

Morgen fahren wir nach Berlin.
(Tomorrow we’re going to Berlin. / We will go to Berlin.)

So using kommt here is natural even though in English you might say “will come”.

Why is it schnell and not something like bald?

schnell focuses on the speed (how fast he comes):

Der Notarzt kommt schnell.
→ He arrives quickly / at high speed.

bald focuses on time relative to now (soon, in a short time), not on speed:

Der Notarzt kommt bald.
→ He will come soon (but not necessarily quickly, maybe in 20 minutes).

Your sentence says the doctor comes quickly, not just soon, so schnell is the right adverb.

Where can schnell go in the sentence? Is Der Notarzt kommt schnell the only option?

In a simple main clause like this, Der Notarzt kommt schnell is the most natural word order. Other placements are possible but change emphasis or sound less natural:

Der Notarzt kommt schnell.
(neutral; standard)
Schnell kommt der Notarzt.
(emphasis on schnell; a bit literary or dramatic.)

You would not normally say:

Der Notarzt schnell kommt. ✗ (incorrect word order in a main clause)

So your version is the normal, neutral choice.

Why is it nicht lange warten and not lange nicht warten?

nicht usually comes before the element being negated. Here, the thing being negated is “lange warten” (wait for a long time), so:

nicht lange warten = not wait for a long time.

lange nicht warten would be understood as something like “wait for a long time not (yet)” in some contexts, or is closer to a different pattern like:

Ich habe ihn lange nicht gesehen.
(I haven’t seen him for a long time.)

That’s a different structure. For your meaning (to prevent a long wait), nicht lange warten is the correct order.

What’s the difference between lange and lang in this kind of phrase?

Both lang and lange can mean “for a long time”, but:

lange is the standard form in neutral written German:
- Er muss nicht lange warten.
lang is more colloquial and common in speech:
- Er muss nicht lang warten.

In everyday conversation, nicht lang warten is very frequent. In careful written German, nicht lange warten is more typical.

What exactly does Notarzt mean, and why is it der Notarzt?

Notarzt is a compound:

Not = emergency, distress
Arzt = doctor (male or generic)

So Notarzt = emergency doctor, typically the physician who comes with an ambulance or emergency service.

Grammatical details:

It’s a masculine noun in standard form: der Notarzt (singular).
Plural: die Notärzte.
Female form: die Notärztin (singular), die Notärztinnen (plural).

Since we’re talking about one (generic) emergency doctor, the nominative singular is der Notarzt.

Could we also say Der Notarzt kommt schnell an? What’s the difference?

Both are possible, but the nuance changes:

Der Notarzt kommt schnell.
→ Focus on the speed of coming / approaching. It’s general and very common.
Der Notarzt kommt schnell an.
→ Emphasizes the moment of arrival at a specific place (hospital, accident site, etc.).

If the context is clearly about reaching a location, kommt schnell an works, but in general descriptions kommt schnell is more neutral and common.