Learn Finnish: Me tehtiin tuli ja grillattiin eväät. - We made a fire and grilled our snacks.

In colloquial Finnish (puhekieli), it is standard to replace the first-person plural verb forms (like teimme and grillasimme) with the passive form. When you use the pronoun me with a passive verb, it just means 'we did' something.

Why is the word for fire tuli in its basic form instead of tulen?

This is a very important rule in spoken Finnish! In standard Finnish, you would say me teimme tulen using the genitive case for the object. But because the spoken version uses the passive verb form (tehtiin), the object must follow the passive rule: the object of a passive verb takes the basic nominative form (tuli).

How is the passive past formed for tehdä to get tehtiin?

Tehdä is a type 2 verb. To form the passive past, you take the stem teh-, add the passive marker -t-, the past tense -i-, and the passive ending -in to get tehtiin.

How does the verb grillata become grillattiin?

Grillata is a type 4 verb. For type 4, 5, and 6 verbs, the passive past is made by taking the infinitive, dropping the final vowel, and adding -ttiin. So grillata becomes grillattiin.