Learn Croatian: Kovač kuje anđela od čelika. - The blacksmith forges an angel out of steel.

Masculine nouns ending in -ao or -eo, like anđeo or posao, underwent a historical change where an original 'l' turned into an 'o' at the end of the word. When we add case endings, the letter isn't at the end of the word anymore, so it reverts back to an 'l'. The stem for all other cases of anđeo is anđel-.

If anđela is the direct object here, why does it take the -a ending?

As the direct object of the verb kuje, the noun must be in the accusative case. For masculine nouns, the accusative form depends on whether the noun is alive (animate) or not. Since an angel is considered an animate being, its accusative form matches the genitive form, which takes the -a ending.

The verb kuje (forges) looks related to kovač (blacksmith). What is its infinitive form?

The infinitive is kovati (to forge). In Croatian, most verbs that end in -ovati drop the -ova- and add -uj- before the personal endings in the present tense. That is why kovati becomes kuje for the third-person singular.

Why is the word for steel, čelik, written here as čelika?