Croatian has three useful demonstrative adjectives. Let's list them and compare with not only English, but also Spanish demonstratives (as they are more similar to Croatian); I'll list with them another adjective with a related meaning:
|onaj (on-)||that over there||aquel/aquella|
They can be used as normal adjectives:
Ona kuća je velika. That house is big.
Marko živi u ovom stanu. Marko lives in this apartment.
Unlike most other adjectives, the three adjectives listed above – ovaj (ov-), taj (t-) and onaj (on-) – cannot get -i in masculine nominative singular. (Recall that the same restriction applies to moj my).
As in English, it's quite common in Croatian to use certain adjectives on their own, without any noun, as pronouns (compare to English each, others, and so on). However, regardless how they are used, words that are originally adjectives still change as adjectives, that is, get case endings for adjectives.
Demonstrative adjectives, in the neuter gender (i.e. ovo, to, etc.) are often used as generic pronouns, in questions, explaining things, etc.; the adjective-used-as-pronoun to is frequently translated with English it:
To je mačka. It's a cat.
Ovo je pas. This is a dog.
I'll call such sentences demonstrative. They behave a bit strange: nouns in them (e.g. mačka, pas) are subjects, so the verb biti (je² +) be agrees with them. It applies to using to with another pronoun as well:
To sam ja. It's me. (lit. ‘It I am.’)
If you use to + adjectives, it's a different type of sentence: you are talking about something else, already known. Now the word to is the subject, be careful that you use the neuter gender of adjectives:
Ovo je teško. This is heavy/hard.
This is completely different than how e.g. pronouns ja I or ti you (singular) behave: with them, you have to think what the pronoun represents, and adjust the gender accordingly. With to you have to use the neuter gender, regardless of what the pronoun represents!
This is very often used to express that something belongs to someone, using possessive adjectives:
To je moje. It's mine.
(Recall that moj gets -e in neuter, since it ends in a Croatian-specific consonant.)
Croatian has the 3rd person neuter pronoun ono it, but demonstrative adjective/pronoun in the neuter gender – to — prevails in use instead.
You can use to (or ovo, etc.), with the verb zvati (zove) call + se² to express what is the name or word for something:
Ovo se zove džep. This is called a pocket.
To ask what is something called, use kako how (again, as in Spanish or Italian):
Kako se to zove (na hrvatskom)? What is that called (in Croatian)?
Although Croatian has no articles, you can use taj (t-) as an adjective, if you want to emphasize that something is strictly defined, already known:
Čekam taj vlak. I'm waiting for that train.
Ta žena je ovdje. That woman is here.
The opposite can be expressed with two adjectives that express that something is not really known:
|jedan (jedn-) one||neki some|
Neka žena je ovdje. A woman is here. (or some woman...)
The adjective jedan (jedn-) one serves as a number – for instance, you can say that you have one son (recall, masculine nouns standing for people or animals change in accusative):
Imam jednog sina. I have one son. (or a son)
The adjective drugi is often translated as English another. While English e.g. another apple is a bit ambiguous, Croatian drugi means not this one, and Croatian uses još + jedan (jedn-) in meaning one more:
Želim drugu jabuku. I want another apple. (a different apple)
Želim još jednu jabuku. I want another apple. (one more)
Croatian has specific demonstrative adverbs for manner (how) and quantity (how much/many) that don't have exact English counterparts:
|ovako in this way, like this||ovoliko this much/many|
|tako in that way, so||toliko so much/many|
|onako in that way, like that||onoliko that much/many|
Out of them, ovako, tako and toliko are most often used. For example:
Ovaj auto je tako brz. This car is so fast.
In fact, Croatian has a wide array of demonstrative adverbs, covering every category of adverbs: destination, origin, reason, location, time, etc. Some of them are frequently used, others less so.
However, certain meanings are expressed with a demonstrative + noun, and the whole phrase gets a special meaning. The noun put (meaning way on its own) is often used in such phrases:
ovaj put this time (around)
taj put that time
Croatian has also demonstrative adjectives corresponding to quality and size:
ovakav (ovakv-) such, like this
ovolik this big
Don't forget these words are adjectives, that is, change in gender, case and number. For example:
Imam ovakvu majicu. I have such a shirt.
Other forms are derived in the same way as for other types of demonstratives, i.e. by replacing ov- with t- or on-.
Don't worry too much about the difference between ovakav (ovakv-) and takav (takv-) – they are often used interchangeably by Croatians.
English has specific time adverbs for ‘on, during this day’ (today) and ‘this night’ (tonight). Croatian has a bit expanded scheme. They all end in -s:
jutros this morning|
večeras this evening
Večeras idemo u restoran. We're going to the restaurant this evening.
The word to is also used in the phrase to jest (where jest is an archaic form of je², the pres-3 of biti).
Another demonstrative, tako, is used in another frequent phrase, i tako dalje. Both are very common expressions, so they have standard abbreviations (the periods are mandatory; matching English abbreviations are also given):
|to jest that is||tj. i.e.|
|i tako dalje and so on||itd. etc.|