Questions & Answers about Joku on tehnyt tämän uuden projektin.
Why is the verb form tehnyt instead of something like tehdänyt?
Tehnyt is the past participle of the Type 2 verb tehdä (to make/do). For Type 2 verbs, you find this form by dropping the final -da or -dä from the infinitive and adding -nut or -nyt. Dropping -dä leaves the stem teh-, and we add -nyt because of vowel harmony (the word has an 'e' and an 'ä').
How does this sentence say 'has made' instead of just 'made'?
The Finnish perfect tense is formed similarly to English: using a helper verb plus a past participle. In Finnish, the helper is olla (to be). Here, on is the helper, and tehnyt is the participle. If the sentence was in the simple past tense ('Someone made'), it would just be Joku teki.
Why do the words for 'this new project' all end in -n (tämän uuden projektin)?
They make up the direct object of the sentence (the thing being made). Because the action of making the project is completely finished, the object takes the accusative case, which looks exactly like the genitive case (adding -n). The describing words tämä (this) and uusi (new) must match the ending of the main noun projekti.
Why does the word uusi (new) change to uuden instead of just ?