Learn Hardcore Croatian: Na sastanku sam predložila novi raspored predavanja. - At the meeting I female suggested a new schedule of lectures.

Both parts together express past tense.
In the sentence, ja is dropped (see next question), but sam predložila still functions as “I proposed”.

Where is “I” in this sentence? Why is there no ja?

Croatian usually omits subject pronouns (ja, ti, on, ona, etc.) if they are clear from the verb.

sam predložila can only mean “I proposed” (1st person singular), so ja isn’t needed.
You can say Ja sam predložila… for emphasis (e.g. I was the one who proposed…), but in neutral speech it’s usually just omitted.

Why does predložila end in -la? What does that -la mean?

The ending -la shows:

Past tense (the l‑participle form).
Gender and number: feminine singular.

So:

predložio = masculine singular (he / I (male) proposed).
predložila = feminine singular (she / I (female) proposed).
predložili = masculine/mixed plural (they proposed).
predložile = feminine plural (they (all women) proposed).

Here, predložila tells us the speaker is female (or the subject is a feminine noun like ona).

How would the sentence change if the speaker were male?

Only the participle changes:

Female speaker: Na sastanku sam predložila novi raspored predavanja.
Male speaker: Na sastanku sam predložio novi raspored predavanja.

Everything else stays the same. The auxiliary sam does not change by gender; only predložila/predložio does.

Why is sam placed after Na sastanku and not right before predložila?

Sam is a clitic (an unstressed short word) and Croatian has a “second position rule”:

Clitics (like sam, si, je, smo, su, se, mi, ti) usually go in the second position in the clause – after the first word or phrase.

So:

Na sastanku sam predložila… (At the meeting I proposed…)
Ja sam na sastanku predložila… (I at the meeting proposed…)
Predložila sam na sastanku… (I proposed at the meeting…)

In each version, sam appears right after the first element of the sentence.

Can I say Predložila sam novi raspored predavanja na sastanku instead? Is that still correct?

Yes, it’s correct and natural. Croatian word order is flexible.

These all work, with slightly different emphasis:

Na sastanku sam predložila novi raspored predavanja.
→ Emphasis a bit on “at the meeting” as the setting.
Predložila sam na sastanku novi raspored predavanja.
→ Neutral: what you did (predložila) comes first.
Predložila sam novi raspored predavanja na sastanku.
→ Slightly more linear, the place comes last.

The basic meaning stays the same: At the meeting, I proposed a new schedule of lectures.

Why is it na sastanku, not u sastanku?

Both na and u can mean “in/at”, but they are used with different types of events and places.

na sastanku = at the meeting (events, gatherings, activities)
Examples: na sastanku, na koncertu, na predavanju, na poslu
u is more for inside a physical space:
u sobi (in the room), u kući (in the house), u zgradi (in the building).

A sastanak is seen as an event rather than a container, so Croatian uses na.

What case is sastanku in, and why does it end in -u?

Sastanku is in the locative case singular.

The base noun is sastanak (meeting).
With na meaning at/on as a location, the following noun goes into the locative.
Masculine nouns like sastanak often take -u in the locative:
- sastanak → na sastanku
- stol (table) → na stolu
- posao (work) → na poslu

So na + locative = at/on (a place or event).

What case is novi raspored, and why does it look like that?

Novi raspored is in the accusative singular, because it’s the direct object of predložila (proposed what?).

Nominative (dictionary form): novi raspored (new schedule).
Accusative masculine inanimate: novi raspored (same form as nominative).

So formally:

(Ja) sam predložila što? → novi raspored.
The question “što?” (what?) triggers the accusative.

Why is it predavanja after raspored, not predavanja in some other form? What case is that?

Predavanja here is genitive plural of predavanje (lecture, class).

The pattern:

raspored čega? → a schedule of what?
This “of what” relationship is expressed by the genitive case.

So:

singular: predavanje (a lecture)
plural nominative: predavanja (lectures)
plural genitive: predavanja (same form in this noun type)

Therefore:

novi raspored predavanja = a new schedule of lectures
Literally: new schedule of-lectures (predavanja as genitive plural).

What is the infinitive of predložila, and what’s its aspect? Is there an “-ing”‑type form?

The infinitive is predložiti, and it is perfective.

predložiti (perfective) = to propose (as a single, completed act).
The related imperfective verb is predlagati = to be proposing, to propose repeatedly/over time.

So:

Na sastanku sam predložila…
→ At the meeting I (once, successfully) proposed…
If you wanted to say I was proposing / I used to propose, you’d use predlagati in the past:
Na sastanku sam predlagala… (female), predlagao (male).

How would I say this sentence in the present tense?

Use the present of predlagati (imperfective) for an ongoing action:

Female speaker: Na sastanku predlažem novi raspored predavanja.
Male speaker: Na sastanku predlažem novi raspored predavanja.

The form predlažem is the same for both genders in the present; gender shows only in the past participle (predložila/predložio, predlagala/predlagao).

Why does the adjective novi come before raspored? Can it come after?

In Croatian, adjectives normally come before the noun they describe:

novi raspored = new schedule
stari raspored = old schedule
važan sastanak = an important meeting

Putting the adjective after the noun is unusual and usually changes the style, emphasis, or meaning (often poetic, fixed phrases, or giving a contrastive emphasis).
So in standard neutral speech you say novi raspored, not raspored novi.