Learn Hardcore Polish: Nie bój się, dopiero zaczynamy lekcję. - Don’t be afraid; we are just starting the lesson.

It’s a 2nd person singular imperative: bój is the imperative of the reflexive verb bać się “to be afraid,” and nie makes it negative: “Don’t be afraid.”
się is the reflexive clitic (unaccented “self” element) required by bać się.
Pronunciation tip: bój sounds like “booy” (Polish ó = English “oo” in “boot”); się sounds like “shyeh.”

Why is it “bój” and not “boisz” or “boi”?

boisz and boi are present‑tense indicative forms (ty boisz się, on/ona boi się = “you are/ he/she is afraid”).
The imperative uses a special stem: bój (się) for “(don’t) be afraid!”
Present conjugation for context: ja boję się, ty boisz się, on/ona boi się, my boimy się, wy boicie się, oni/one boją się.
Imperatives: ty bój się, wy bójcie się. (First‑person plural “let’s be afraid” exists—bójmy się—but is rarely useful.)

Where does “się” go in a sentence like this?

In imperatives, the reflexive clitic się follows the verb: Nie bój się.
You don’t say “Nie się bój.” In standard Polish, się cannot start the clause.
With different structures, się may appear after the first stressed word (second‑position clitic behavior), e.g., Proszę się nie bać “please don’t be afraid.”

What nuance does “dopiero” add?

dopiero means “only/just now,” highlighting that something is at a very early stage or happening later than expected.
Compare:
- Dopiero zaczynamy lekcję = “We’re only just starting the lesson (so there’s no reason to worry).”
- Już zaczynamy = “We’re already starting (so get ready).”
- Właśnie zaczynamy = “We’re just now starting” (neutral “right now” focus).
- Tylko is “only” in the sense of limitation/quantity, not timing; dopiero is the temporal “only just.”

Why is it “zaczynamy” (present) instead of “zacznijmy” (let’s start)?

zaczynamy is the present indicative “we are starting,” which in context can function like a gentle announcement.
zacznijmy is the 1st person plural imperative “let’s start.”
With dopiero, you want the “we’re only just starting” nuance, so dopiero zaczynamy fits best. “Dopiero zacznijmy” is not idiomatic.

How does verbal aspect play into this (zaczynać vs. zacząć)?

Imperfective: zaczynać (we focus on the process or repeated action) → zaczynamy “we’re starting (now/only just).”
Perfective: zacząć (completed single start) →
- Future: dopiero zaczniemy = “we will only start (later, not yet),”
- Past: dopiero zaczęliśmy = “we’ve only just started.”

Why is “lekcję” in that form, and which case is it?

lekcję is the accusative singular of lekcja (a feminine noun). Feminine nouns ending in -a typically take -ę in the accusative singular.
The verb zaczynać/zacząć takes a direct object in the accusative: zaczynamy [co?] lekcję = “we’re starting the lesson.”

But doesn’t “bać się” take the genitive? Why not “lekcji” after “się”?

Correct: bać się governs the genitive when it has an object (e.g., Boję się lekcji = “I’m afraid of the lesson,” genitive: lekcji).
In this sentence, lekcję is the object of zaczynamy, not of bać się. So it’s accusative, and its placement after the second clause makes that clear: … dopiero zaczynamy lekcję.

How do you pronounce the whole sentence naturally?

Stress is (almost always) on the second‑to‑last syllable of each word.
Approximation:
- Nie [nyeh]
- bój [booy]
- się [shyeh]
- pause/comma
- dopiero [do-PYE-ro]
- zaczynamy [za-chy-NA-my] (cz = “ch” in “church” but harder; y = Polish “ɨ,” not English “ee”)
- lekcję [LEK-tsyeh] (final ę is often just a slightly nasal “eh” in casual speech)
Put it together with a small pause at the comma: “Nyeh BOOY shyeh, do-PYE-ro za-chy-NA-my LEK-tsyeh.”

Why is there a comma after “Nie bój się”?

Polish uses a comma to separate two independent clauses/intonation units even without a conjunction: Nie bój się, …
- dopiero zaczynamy lekcję.
The pause mirrors natural speech; the comma is standard and recommended here.

How do I say this to more than one person or politely?

To a group (informal plural): Nie bójcie się, dopiero zaczynamy lekcję.
Polite singular (to one adult):
- Proszę się nie bać, dopiero zaczynamy lekcję. or
- Niech się pan/pani nie boi, dopiero zaczynamy lekcję.
Polite plural (to multiple adults): Niech się państwo nie boją, dopiero zaczynamy lekcję.

Can I change the word order around “dopiero” and “lekcję”?

Yes, but the nuance shifts:
- Dopiero zaczynamy lekcję (neutral; focuses on “only just now”).
- Zaczynamy dopiero lekcję (slight emphasis on “it’s the lesson that we’re only just starting,” often contrastive).
- Lekcję dopiero zaczynamy (marked/contrastive emphasis on “the lesson”).
All are grammatical; default choice is the original.

What’s the difference between “Nie bój się” and “Nie martw się”?

Nie bój się = “Don’t be afraid” (fear).
Nie martw się = “Don’t worry” (anxiety/concern).
They overlap in use as reassurance; choose based on whether the emotion is fear (bój) or worry (martw).

Why is there an “ó” in “bój,” but “boisz” has just “o”?

It’s a historical spelling alternation (ó ~ o) common in Polish: bój vs boję/boisz/boi.
You’ll see similar patterns in other words (e.g., stół → stołu).
Pronunciation: ó is always like “u” in “boot.” The spelling alternation is lexical—learn it with the verb.

Can I drop “się” and just say “Nie bój”?

No. bać się is reflexive by nature; without się it’s ungrammatical here.
Note: bój without się is also a common noun meaning “battle,” which is unrelated to the verb “to be afraid.”

Why is the final “ę” in “lekcję” sometimes not very nasal?

Word‑final ę is often realized as a plain “e” with light nasalization in everyday speech, so lekcję often sounds like “lekcjeh.”
Before certain consonants, ę can surface more clearly nasal (e.g., w ręce). Here, at the end, it’s subtle.