Learn Hardcore Czech: Když jdu pozdě, jsem nervózní a spěchám po ulici. - When I am late, I am nervous and I hurry along the street.

a question word:
- Kdy jdeš do práce? – When are you going to work?
or used in some fixed expressions, but not to introduce a normal “when”-clause like in your sentence.

So:

✅ Když jdu pozdě, jsem nervózní.
❌ Kdy jdu pozdě, jsem nervózní. (ungrammatical in this meaning)

Why is it jdu pozdě (I go late) and not jsem pozdě (I am late)?

In Czech, being late is often expressed with a verb of motion:

jdu pozdě – I’m late (when I’m going on foot)
jedu pozdě – I’m late (when I’m going by car/bus/train etc.)
přijdu pozdě – I’ll arrive late (on foot)
přijedu pozdě – I’ll arrive late (by vehicle)

Saying jsem pozdě is not natural Czech in this sense; you normally tie “lateness” to the action of going/coming.

So Když jdu pozdě is understood as “When I’m (going and therefore) late,” not literally “When I go late.”

Could I say Když přijdu pozdě instead of Když jdu pozdě? Is there a difference?

Yes, you can, and it’s often more natural depending on what you mean:

Když jdu pozdě – focuses on the process of going somewhere late.
Když přijdu pozdě – focuses on the moment of arrival being late.

Typical use:

Když přijdu do práce pozdě, jsem nervózní.
= When I arrive at work late, I’m nervous.

In isolation, both are understandable:

Když jdu pozdě, jsem nervózní… – speaking about the whole walk while you are late.
Když přijdu pozdě, jsem nervózní… – speaking about the fact that you arrive late.

In everyday speech, přijdu pozdě is very common when talking about being late to some event or place.

Why is the verb in the present tense (jdu, jsem, spěchám) when in English we might also think of future situations?

Czech often uses the present tense in když-clauses to talk about:

general, repeated situations (like “whenever”)
sometimes even future time, if it’s a general rule

Here, your sentence is a general statement:

Když jdu pozdě, jsem nervózní.
= When(ever) I’m late, I’m nervous.

Compare:

Když mám hlad, jím. – When I’m hungry, I eat.
Když mám čas, zavolám ti. – When I have time, I’ll call you. (future in meaning, but present in form)

So the present tense in Czech is normal here and matches the English habitual “when I’m late, I’m nervous.”

Why is there a comma before jsem nervózní a spěchám po ulici?

Czech uses a comma between dependent clauses and the main clause.

Když jdu pozdě – this is a subordinate clause (introduced by když).
jsem nervózní a spěchám po ulici – this is the main clause.

Rule: Put a comma before the když-clause ends (i.e., between the two clauses):

Když jdu pozdě, jsem nervózní a spěchám po ulici.

If you reverse the order, you also use a comma:

Jsem nervózní a spěchám po ulici, když jdu pozdě.

Could I say Já jsem nervózní instead of just jsem nervózní? Why is já omitted?

Yes, you can say Já jsem nervózní, but the pronoun is usually omitted because the verb ending already shows the person:

jdu = I go
jsem = I am
spěchám = I hurry

So the subject já is normally dropped unless you want to emphasize it:

Já jsem nervózní, ne on. – I am nervous, not him.

In your neutral sentence, Když jdu pozdě, jsem nervózní… sounds more natural than Když jdu pozdě, já jsem nervózní…, which feels a bit stressed/contrasty.

What is the nuance of spěchat? Is it exactly the same as “to hurry”?

Spěchat corresponds well to English to hurry, but has a few common uses:

Move fast / rush:
- Spěchám po ulici. – I’m hurrying along the street.
Be in a hurry (have little time):
- Spěchám, nemám čas. – I’m in a hurry, I don’t have time.
Impatient sense:
- Nespěchej! – Don’t rush / Don’t be in such a hurry.

There is also pospíchat, which is very similar to spěchat; in many everyday contexts they’re interchangeable:

Spěchám domů. ≈ Pospíchám domů.

Your sentence uses spěchám po ulici in the physical “rushing along the street” sense.

Why is it po ulici and not just ulicí or na ulici?

All three exist, but with slightly different nuances:

po ulici (+ locative) – “along / up and down / around the street”
- spěchám po ulici – I’m hurrying along the street (movement over the area or length of the street)
ulicí (instrumental, without preposition) – “along / down the street”
- spěchám ulicí – also “I’m hurrying down the street,” a bit more literary/stylish.
na ulici – “on the street / in the street” (location, not so much direction)
- Jsem na ulici. – I’m on the street / outside.
- Děti si hrají na ulici. – The children are playing in the street.

In your sentence, po ulici emphasizes movement along the street, which goes naturally with spěchat (hurrying).

Does nervózní change for gender, or is it the same for “I” whether I’m male or female?

Nervózní is an adjective that has the same form for masculine and feminine singular in the predicate position:

Jsem nervózní. – I am nervous. (said by a man or a woman)
On je nervózní. – He is nervous.
Ona je nervózní. – She is nervous.

It changes for plural and for other cases, e.g.:

Jsme nervózní. – We are nervous.
vidím nervózního muže – I see a nervous man (here it changes to nervózního because of case and gender).

But in your sentence, for “I am nervous,” you always say Jsem nervózní, regardless of the speaker’s gender.

Could the word order be Když jdu pozdě, spěchám po ulici a jsem nervózní? Does word order change the meaning?

Yes, you can change the order:

Když jdu pozdě, jsem nervózní a spěchám po ulici.
Když jdu pozdě, spěchám po ulici a jsem nervózní.

Both are grammatically correct and have nearly the same meaning. The difference is very subtle and mostly about what you mention first:

First version: being nervous is foregrounded slightly more.
Second version: the physical action of hurrying comes first.

Czech word order is relatively flexible; basic meaning stays the same, but focus and emphasis can shift depending on the order.

Is pozdě an adjective like “late,” or something else?

Pozdě is an adverb, meaning late (in time):

Jdu pozdě. – I’m late (I’m going late).
Přišel pozdě. – He came late.

The adjective corresponding to it is pozdní:

pozdní večeře – a late dinner
pozdní hodina – a late hour

So:

You use pozdě with verbs (arrive late, go late, come late).
You use pozdní with nouns (late dinner, late show, late train, etc.).

Your sentence correctly uses the adverb: jdu pozdě.

What’s the difference between pozdě and později?

Both are adverbs, but:

pozdě = late (too late / not on time)
- Jdu pozdě. – I am late.
později = later (at a later time, not necessarily too late)
- Přijdu později. – I’ll come later.

So:

Když jdu pozdě, jsem nervózní. – When I’m late (not on time), I’m nervous.
Přijdu později, protože mám práci. – I’ll come later because I have work (not necessarily late in the sense of “oops, I missed the time”).