Breakdown of Trebuie să spun adevărul.
să
to (subjunctive marker)
trebui
to have to / to be needed (with a dative: to need)
spune
to say / to recite
adevărul
the truth
Questions & Answers about Trebuie să spun adevărul.
Why doesn't trebuie change its ending to match I?
Trebuie is a special verb that doesn't change its form depending on who is speaking. Instead of saying I must, Romanian essentially says it is necessary. The person who has to do the action is shown by the second verb, spun (I tell).
What is the purpose of să here?
English uses the infinitive after have to (I have to tell). Romanian uses a different structure: the linking word să followed by a conjugated verb. You can think of Trebuie să spun literally as It is necessary that I tell.
Since trebuie doesn't change, how do we know who has to tell the truth?
We know who has to do it because of the verb after să. The verb a spune (to tell) is conjugated as spun for the first person (I tell). If it were you have to tell the truth, the sentence would be Trebuie să spui adevărul.
How do you form adevărul (the truth)?
In Romanian, the word for the is usually added to the end of the noun. The base noun here is adevăr (truth). By adding the definite article suffix -ul to the end, we get adevărul (the truth).