Learn Finnish: Jos kukaan selviytyy tästä helleaallosta, se on ihme. - If anyone survives this heatwave, it is a miracle.

In conditional clauses starting with jos (if), negative pronouns like kukaan and mikään are used in an affirmative way to mean 'anyone' or 'anything'. Using kukaan here adds a layer of doubt, emphasizing 'if anyone at all'. If you used joku, it would sound more specific, like 'if a certain someone survives'.

Why is tästä helleaallosta in the elative case ending in -sta?

The verb selviytyä (to survive, to cope with) requires its object to be in the elative case, which uses the endings -sta or -stä. In Finnish logic, you survive out of an ordeal.

Does the verb always stay in the singular form after kukaan?

Yes. Just like 'anyone' or 'nobody' in English, kukaan is grammatically singular. That is why we use the third-person singular form selviytyy rather than a plural form.

Could I use the verb selviää here instead of selviytyy?

Yes, selvitä and selviytyä are often interchangeable when talking about surviving a situation. However, selviytyä specifically emphasizes the struggle or effort of making it through a physical or mental hardship, which makes it a perfect fit for an extreme heatwave.