Learn Finnish: Talvella aamu on hyvin pimeä. - In winter the morning is very dark.

In Finnish, the -ssa ending is mostly used for being physically inside a space. For expressing when something happens using seasons or parts of the day, Finnish instead uses the -lla ending, which normally translates to 'on' or 'at'. That is why 'in winter' is talvella.

Why does the dictionary word talvi (winter) change to talve- before adding the -lla ending?

Many basic Finnish words that end in -i, like talvi, change that i to an e when you add grammatical endings to them. So talvi changes to the base form talve-, and then you add -lla to make talvella.

Doesn't the word hyvin usually mean 'well'? Why does it mean 'very' here?

Yes! Hyvin is the adverb form of hyvä (good), so it usually translates to 'well'. However, when it is placed directly before an adjective like pimeä (dark), it acts as an intensifier meaning 'very'. You can also use words like tosi or erittäin to say 'very' in Finnish.

Is it okay to change the word order and say Aamu on hyvin pimeä talvella?