Questions & Answers about Minä väitän olevani muita sinnikkäämpi.
Why is the word olevani used here instead of että olen or minun olevan?
This sentence uses the referative construction (partisiippirakenne) to replace an että clause. Because the subject of the main clause (Minä) is the same as the subject of the embedded clause, we drop the genitive pronoun minun. Instead, we take the participle form olevan and attach the matching possessive suffix -ni, creating olevani.
Why is the word for 'others', muita, in the partitive plural case?
It is being used for comparison to mean 'than others'. In Finnish, you can express 'more than X' by putting X in the partitive case right before the comparative adjective (muita sinnikkäämpi). Alternatively, you could use kuin (than) with the nominative case: sinnikkäämpi kuin muut.
Does the partitive comparison word muita have to come before the adjective sinnikkäämpi?
Yes. When you use the partitive case to say 'than X' instead of using kuin, the partitive word must be placed directly before the comparative adjective. Saying sinnikkäämpi muita is grammatically incorrect.
How does the basic adjective sinnikäs (persistent) change into the comparative form sinnikkäämpi?