Breakdown of Postilaatikko on täynnä mainoksia.
Questions & Answers about Postilaatikko on täynnä mainoksia.
Täynnä is a special adjective‐like form that takes a complement in the partitive case (here mainoksia). It expresses the idea “full of something.”
Täysi is a regular adjective (“full”) and would normally take its noun in nominative or genitive (e.g. täysi laatikko = “a full box”), but doesn’t combine with a partitive object to mean “full of X.”
Make both subject and verb plural:
Postilaatikot ovat täynnä mainoksia.
Here postilaatikot is the nominative plural of postilaatikko, and ovat is the third person plural of olla.
Finnish has fairly flexible word order, but the neutral order is Subject–Verb–Complement (S-V-C). So Postilaatikko on täynnä mainoksia is standard.
You could say Täynnä mainoksia on postilaatikko to stress täynnä mainoksia, but that sounds poetic or marked.
In Finnish, double vowels are long.
– laatikko: [laːtikːo] (long aa)
– täynnä: [tæʏ̯nːæ] (long ä)
Vowel length can change meaning, so it’s important to hold the sound slightly longer than a single vowel.