U tom frižideru uvijek ima mjesta za vodu i kolače, ali danas nema mjesta za veliki lonac juhe.

Because u means in here, and when u expresses location, it takes the locative case.

So:

• frižider = dictionary form
• u frižideru = in the fridge

A useful contrast:

• u tom frižideru = in that fridge → location, so locative
• u taj frižider = into that fridge → movement, so accusative

Taj is the basic dictionary form of the demonstrative meaning that. In Croatian, words like this have to agree with the noun in gender, number, and case.

Since frižideru is:

• masculine
• singular
• locative

taj changes to tom.

So:

• taj frižider = that fridge
• u tom frižideru = in that fridge

Croatian does not have articles like English the and a/an.

Definiteness is usually understood from:

• context
• word order
• demonstratives such as taj, ovaj, onaj

So frižider can mean a fridge or the fridge, depending on context, and tom frižideru makes it more specific: in that fridge.

This is a very common Croatian pattern. Ima and nema are often used impersonally to mean that something exists, is available, or there is/isn't enough of it.

So ima mjesta means there is room / there is space.

It is not literally built the same way as English there is, but it functions that way in practice.

Common examples:

• Ima vremena. = There is time.
• Nema problema. = There is no problem / No problem.
• Ima mjesta. = There is room.

Here mjesta is the genitive singular of mjesto.

This is the normal form in the expression ima mjesta / nema mjesta, which means there is room / there isn't room.

So although mjesta can look like a plural form in other contexts, here it is singular in meaning: room/space, not places.

Compare:

• mjesto = place, spot
• ima mjesta = there is room / there is space

Because za in the sense of for normally requires the accusative case.

So:

• voda → vodu
• kolači → kolače

That is why the sentence has za vodu i kolače.

Because they belong to different noun patterns.

• voda is a feminine singular noun, so its accusative singular is vodu
• kolači is a masculine plural noun, so its accusative plural is kolače

So both are in the accusative, but they do not look the same because Croatian endings depend on gender, number, and declension pattern.

Because za meaning for takes the accusative, and veliki lonac is the direct object of that preposition.

Also, lonac is masculine inanimate singular, and in that pattern the accusative often looks the same as the nominative.

So:

• nominative: veliki lonac
• accusative: veliki lonac

The adjective also matches:

• veliki = masculine singular accusative inanimate here

Because juhe depends on lonac.

Lonac juhe means a pot of soup, and Croatian often uses the genitive after a container noun to show what it contains.

Very common patterns are:

• čaša vode = a glass of water
• boca vina = a bottle of wine
• lonac juhe = a pot of soup

So in za veliki lonac juhe, the whole phrase veliki lonac juhe is governed by za, but inside that phrase juhe stays genitive because it depends on lonac.

Because ali means but, and in Croatian it normally introduces a new clause that is separated by a comma.

Here the sentence has two coordinated parts:

• U tom frižideru uvijek ima mjesta za vodu i kolače
• ali danas nema mjesta za veliki lonac juhe

So the comma before ali is standard punctuation.

Croatian often leaves out subject pronouns when they are not needed, and in this kind of expression ima / nema is especially impersonal.

English says there is or it has room in some contexts, but Croatian simply says:

• ima mjesta
• nema mjesta

You do not normally add a pronoun here.

Yes. Croatian word order is fairly flexible, and speakers can move words for emphasis or style.

The order in the sentence is natural and neutral:

• U tom frižideru uvijek ima mjesta...
• ...ali danas nema mjesta...

But other orders are possible, for example:

• Danas nema mjesta za veliki lonac juhe.
• U tom frižideru ima uvijek mjesta... — possible, but less neutral

In general, the original sentence sounds very natural for everyday Croatian.

Yes. Frižider is very common in everyday speech.

You should also know hladnjak, which is often preferred in more standard or formal Croatian.

So both are useful:

• frižider = very common colloquial everyday word
• hladnjak = standard/formal word for fridge

A learner should recognize both.