Learn Finnish: Huomautin pomolle lattialle kaatuneesta vedestä. - I pointed out the water spilled on the floor to the boss.

The verb huomauttaa (to point out or remark) requires the same grammatical case as verbs of warning like varoittaa. When you bring someone's attention to something, or warn them about it, the topic takes the elative case (-sta/-stä). Here, you are pointing out the water, so it becomes vedestä.

How does the word kaatuneesta work here?

It is the past active participle (the -nut/-nyt form) of the verb kaatua (to spill or fall over), acting as an adjective to describe the water. Because modifiers must agree with their nouns, and the water is in the elative case (vedestä), kaatunut also takes the elative ending and becomes kaatuneesta.

Why does the sentence use lattialle (onto the floor) instead of lattialla (on the floor)?

The verb kaatua (to spill) expresses a movement that ends up onto a surface. Finnish grammar focuses heavily on the direction of the action rather than just the final resting place, so it requires the directional allative case (-lle) rather than a static location case.

Why is the boss in the allative case (pomolle)?