Learn Croatian: Iako je teško, bacit ću sve što je materijalni višak. - Although it is difficult, I will throw away everything that is material excess.

When a relative pronoun refers back to an indefinite pronoun like sve (everything), nešto (something), or ništa (nothing), Croatian requires the use of što. If you were referring back to a regular noun, you would use koji.

Why is the verb written as bacit instead of the full infinitive baciti?

In the Croatian future tense, when an infinitive verb ending in -ti is placed immediately before the auxiliary verb (ću, ćeš, etc.), the final -i must be dropped. If you reversed the word order, you would keep the -i (for example: ja ću baciti).

Is baciti a perfective or imperfective verb?

It is a perfective verb, meaning it describes a single, completed action. The speaker intends to throw the excess away and be done with it. If they were talking about an ongoing habit of throwing things, they would use the imperfective counterpart bacati.

Why is materijalni višak in the nominative case if it is the thing being thrown away?

The pronoun sve is the actual direct object of the throwing. Inside the relative clause, materijalni višak follows the verb je (is). The verb "to be" simply equates two things, so the noun following it stays in the nominative case.