Breakdown of Ему ни интересно, ни скучно, он просто сомневается.
он
he / it (for a masculine noun) / it (for a neuter noun)
ему
to him, to it
просто
simply, just
скучно
bored / boring
Questions & Answers about Ему ни интересно, ни скучно, он просто сомневается.
How does ни ..., ни ... work in this sentence?
It translates to "neither ... nor". Notice that there is a comma before the second ни; this is a strict punctuation rule in Russian when using double coordinating conjunctions.
Doesn't ни ..., ни ... usually require a negative verb with не? Why is there no не here?
You are right! Normally, Russian requires double negation (e.g., Он не пьёт ни чай, ни кофе). However, the first half of this sentence is an impersonal state using adverbs (интересно, скучно). Because it's in the present tense, the verb "to be" is completely omitted, which means there is simply no verb here to attach a не to!
Why does the sentence use Ему (dative) at the beginning, but он (nominative) in the second half?
The sentence links two different types of clauses. The first expresses a feeling or state using an impersonal construction: Ему интересно literally means "It is interesting to him". The second half uses a regular active verb (сомневается), which requires a standard nominative subject (он).
What is the infinitive of сомневается and why does it have a reflexive -ся ending?