Minä heitän kirjan.

Yes. In Finnish, the subject pronoun is often omitted because the verb ending already shows the person.

So:

• Minä heitän kirjan.
• Heitän kirjan.

both mean I throw / I am throwing the book.

Including minä can make the subject clearer or more emphatic, a bit like saying I throw the book.

The -n marks first person singular: I.

So:

• heitän = I throw
• heität = you throw
• heittää = he/she throws
• heitämme = we throw
• heitätte = you (plural) throw
• heittävät = they throw

This is why Finnish often does not need the pronoun minä.

The dictionary form is heittää, meaning to throw.

This verb changes a little when conjugated:

• heittää → dictionary form
• heitän → I throw

The change from tt to t is a common Finnish pattern called consonant gradation.

Because Finnish verbs do not always keep exactly the same stem in all forms.

With heittää, the stem changes when you add personal endings:

• heittää
• heitän

Here, tt becomes t in this form. That is normal for many verbs in Finnish.

A learner does not need to memorize the technical details immediately, but it is useful to notice that the verb stem can change when conjugated.

Because kirjan is the correct object form here.

In this sentence, the speaker is throwing the whole book as a complete object, so Finnish uses the total object form. For a singular noun like kirja, that usually looks like the genitive form:

• kirja = book
• kirjan = the book / a whole book as the object

So heitän kirjan means you are throwing the entire book, not just doing some incomplete action involving a book.

Functionally, it is the object form, often called the accusative in grammar discussions. But for many singular nouns, that object form looks exactly like the genitive.

So in practice:

• kirjan has the same form as the genitive singular
• but in this sentence it is being used as the object

This is a very common source of confusion for English speakers. A simple way to think of it is:

• kirjan here = the book as a complete object

Yes, it would suggest a different kind of action.

• heitän kirjan = I throw the whole book, a complete event
• heitän kirjaa = I am throwing a book / the book in a more ongoing, incomplete, or indefinite sense

The -a/-ä partitive form often appears when the action is incomplete, repeated, or not directed at a complete whole.

For beginners, the important contrast is:

• kirjan = total object
• kirjaa = partitive object

It can mean either, depending on context.

Finnish present tense often covers both:

• I throw the book
• I am throwing the book

Finnish does not usually make the same strict present simple vs. present continuous distinction that English does.

Finnish does not have articles like English a/an or the.

So kirja can mean:

• a book
• the book

and the exact meaning depends on context.

In Minä heitän kirjan, the context tells you whether it is a book or the book, though English usually has to choose one.

Yes. Finnish word order is fairly flexible, although Minä heitän kirjan is the most neutral order here.

Possible variations include:

• Heitän kirjan. = neutral, very common
• Kirjan heitän. = emphasizes the book
• Minä kirjan heitän. = stronger emphasis, less neutral

English relies more heavily on word order for basic meaning, but Finnish uses endings to show grammatical roles, so word order can be changed for emphasis.

A simple rough guide is:

• Minä ≈ MIH-nah
• heitän ≈ HAY-tan (with ä like the vowel in cat, but cleaner and shorter)
• kirjan ≈ KEER-yan

A few useful pronunciation notes:

• ä is not the same as English a
• j in Finnish sounds like English y
• stress usually falls on the first syllable: MI-nä, HEI-tän, KIR-jan

At the beginner stage, keeping minä can be helpful because it makes the structure easier to see:

• minä = I
• heitän = throw-I
• kirjan = the book / a whole book as object

So it is good for learning, even though natural Finnish often drops the pronoun. Over time, you will get used to sentences like Heitän kirjan without minä.