In Dutch, the diminutive is not merely restricted to nouns and exist in numerals (met z'n tweetjes, "the two of us"), pronouns (onderonsje, "tête-à-tête"), verbal particles (moetje, "shotgun marriage"), and even prepositions (toetje, "dessert"). Most notable however, are the diminutive forms of adjectives and <answer>adverb</answer>s. The former take an diminutive ending and thus functions as a noun, the latter remain <answer>adverb</answer>s and have always the diminutive with the -s appended, e.g. adjective: groen ("green") → noun: groentje ("rookie"); <answer>adverb</answer>: even ("just") → <answer>adverb</answer>: eventjes ("just a minute").
When the diminutive ending "-tjes" is added to the adverb "even," as what part of speech does it function?
adverb