Kuivaamme seinän niin, että kosteus ei pilaa omaisuutta.

Because kuivaamme already includes we. The ending -mme marks first-person plural.

So:

• kuivata = to dry
• kuivaamme = we dry / we are drying

Finnish often leaves subject pronouns out when the verb ending already makes the subject clear. You can say Me kuivaamme, but that adds emphasis, like we are the ones drying it.

The basic form is kuivata, meaning to dry.

Kuivaamme is:

• present tense
• first-person plural
• active voice

So it means we dry or we are drying. Finnish present tense often covers both of those English meanings.

Because seinän is the object form used here.

In this sentence, the wall is the thing being dried, so it is the object. In Finnish, a singular total object often appears in an -n form in affirmative sentences. That is why you get seinän.

So:

• seinä = wall
• seinän = the wall, as a whole object

Many learners notice that this looks like the genitive form, and that is true in terms of shape.

Yes, but it would change the nuance.

• Kuivaamme seinän = we dry the wall as a whole / with a completed, bounded sense
• Kuivaamme seinää = we are drying the wall / some of it / the action is ongoing or incomplete

So seinää would use the partitive object, while seinän presents the wall more as a whole target of the action.

Here niin, että works like so that in English.

It links the first clause to a result or intended result:

• Kuivaamme seinän = we dry the wall
• niin, että kosteus ei pilaa omaisuutta = so that moisture does not ruin property

So it shows what the drying is meant to achieve, or what result it leads to.

Because että kosteus ei pilaa omaisuutta is a subordinate clause.

In Finnish, subordinate clauses are normally separated from the main clause with a comma. So the comma here is standard punctuation.

Finnish makes negatives with a separate negative verb plus the main verb.

Here:

• ei = negative verb, third-person singular
• pilaa = main verb in its negative form

The subject is kosteus (moisture), which is third-person singular, so Finnish uses ei.

A useful set to remember is:

• en = I do not
• et = you do not
• ei = he/she/it does not
• emme = we do not
• ette = you (plural) do not
• eivät = they do not

In this verb, the negative form pilaa happens to look the same as the positive third-person singular form, which can be confusing at first.

Because the object of a negative clause is usually in the partitive in Finnish.

Here the clause is:

• kosteus ei pilaa omaisuutta = moisture does not ruin property

Since it is negative (ei pilaa), the object becomes omaisuutta.

Compare:

• pilaa omaisuuden = ruins the property
• ei pilaa omaisuutta = does not ruin property

So the partitive here is mainly triggered by the negation.

It is partitive singular.

The basic form is omaisuus. Even though English might use property or belongings, Finnish often uses this singular noun for the general idea of someone's possessions or property.

So:

• omaisuus = property, belongings
• omaisuutta = property/belongings in the partitive singular

Because kosteus is the subject of the subordinate clause:

• että kosteus ei pilaa omaisuutta

In ordinary Finnish clauses, the subject is usually in the nominative, which is the basic dictionary form.

So:

• kosteus = moisture
• it is the thing doing the action of not ruining

Yes. Jotta is another common way to say so that / in order that.

For example, a learner may also see:

• Kuivaamme seinän, jotta kosteus ei pilaa omaisuutta.

That version sounds a bit more directly like purpose. The original niin, että is also natural, and it highlights the resulting situation.