Jeśli nie zapomnę o skierowaniu, jutro rano znowu pójdę do laboratorium.

Yes. Jeśli and jeżeli both mean if.

• jeśli is very common and natural in everyday speech
• jeżeli can sound a bit more formal or careful

In this sentence, Jeśli nie zapomnę o skierowaniu... means If I don't forget the referral...

Both are correct here.

Because zapomnę comes from the perfective verb zapomnieć, and it refers to a single completed future event: I will forget.

Compare:

• zapomnieć → perfective → zapomnę = I will forget
• zapominać → imperfective → zapominam = I forget / I am forgetting / I tend to forget

Here the speaker is talking about one possible future situation, so nie zapomnę is the natural choice.

This is a very common point of confusion for English speakers.

In Polish, Jeśli nie zapomnę is completely normal. Polish does not follow the same rule as English here.

Also, with perfective verbs like zapomnieć, forms that look like present tense actually have future meaning:

• zapomnę = I will forget
• pójdę = I will go

So the whole sentence is about the future, and that is perfectly normal in Polish.

Skierowaniu is in the locative singular.

That is because the phrase is:

• zapomnieć o czymś = to forget about something

The preposition o here requires the locative.

So:

• skierowanie = nominative
• o skierowaniu = locative after o

This construction means something like to forget about the referral / fail to remember the referral.

Sometimes yes, but the nuance is a bit different.

• zapomnieć o czymś = to forget about something, to fail to keep it in mind
• zapomnieć coś = to forget something, often in the sense of leaving it behind or not bringing it

In this medical context, nie zapomnę o skierowaniu sounds natural and careful. It suggests I’ll remember the referral.

If you wanted to stress the physical act of forgetting to take it with you, nie zapomnę skierowania may also be heard, but o skierowaniu is very standard here.

Here skierowanie most likely means a medical referral or doctor’s order/referral form.

For example, in Poland you may need a skierowanie for:

• lab tests
• a specialist visit
• some medical procedures

So in this sentence it is not about direction in the ordinary sense. It is a medical document.

Because jutro and rano are both adverbial time expressions.

• jutro = tomorrow
• rano = in the morning / morning-time

Together, jutro rano simply means tomorrow morning.

This kind of expression often has no preposition in Polish:

• dziś rano = this morning
• jutro rano = tomorrow morning
• wczoraj rano = yesterday morning

So jutro rano is just the normal way to say it.

Znowu means again.

Yes, znów is also possible. It means the same thing. The difference is mostly stylistic:

• znowu = very common, everyday
• znów = slightly shorter, sometimes a bit more literary or simply more compact

So you could also say:

• Jeśli nie zapomnę o skierowaniu, jutro rano znów pójdę do laboratorium.

That would mean the same thing.

Pójdę is the future form of pójść, a perfective verb meaning to go for one completed trip.

In many contexts, pójdę is just the normal way to say I will go, especially when talking about going somewhere for a purpose.

It does not always strongly mean walking on foot in everyday usage. Very often it simply means I’ll go.

If you specifically wanted to emphasize going by vehicle, you might say:

• pojadę = I’ll go / I’ll drive / I’ll ride there

But with a place like a lab, pójdę do laboratorium sounds very natural.

The preposition do takes the genitive case.

So do laboratorium means to the laboratory.

A useful detail: nouns like laboratorium ending in -um often keep the same form in the singular across cases. So even though it is genitive here, the word still looks like laboratorium.

That is why you get:

• laboratorium = laboratory
• do laboratorium = to the laboratory

Because Polish normally uses a comma to separate a subordinate clause from the main clause.

Here:

• Jeśli nie zapomnę o skierowaniu = subordinate if clause
• jutro rano znowu pójdę do laboratorium = main clause

So the comma is required.

You would also keep the comma if the order were reversed:

• Jutro rano znowu pójdę do laboratorium, jeśli nie zapomnę o skierowaniu.

Polish word order is fairly flexible, but different orders create different emphasis.

The given order is very natural and neutral:

• Jeśli nie zapomnę o skierowaniu, jutro rano znowu pójdę do laboratorium.

This presents the condition first, then the time, then again, then the action.

Other orders are possible, for example:

• Jeśli nie zapomnę o skierowaniu, znowu jutro rano pójdę do laboratorium.
• Jutro rano znowu pójdę do laboratorium, jeśli nie zapomnę o skierowaniu.

These are still understandable, but the emphasis shifts slightly. For learners, the original word order is a very good model to follow.