Heittomerkkiä verbien taivutuksessa

[Woods]

maukua

indikatiivi: minä mau'un, minä mau'uin, mau'utaan/ei mau'uta, on mau'uttu / ei ole mau'uttu

imperatiivi: (sinä) mau'u!

What are these apostrophes for?


Another quick one:

I am looking at that phrase "Olei aikeissa soittaa sinulle."

Is the first word some kind of dialect or a mistake? Maybe it should be "olin"? I guess the meaning would have been "I was just thinking of calling you"?

(It is also strange to me that aikeissa is in the plural, but I guess that's just the way it is :)

[Naava]

maukua

indikatiivi: minä mau'un, minä mau'uin, mau'utaan/ei mau'uta, on mau'uttu / ei ole mau'uttu

imperatiivi: (sinä) mau'u!

What are these apostrophes for?

They show where the syllable break is. It matters because it affects the pronunciation. I'm not sure how to best describe it or if my attempt is even correct, but when I think of how I say these words, there's a small pause (perhaps even a short glottal stop) or a light secondary stress after the apostrophe.

Separating the vowels with an apostrophe also helps keeping the word more similar to its basic form, which makes reading and recognising it easier. The apostrophe is always put in the place of lost consonant: maukua -> *maukun -> mau'un; vaaka -> *vaakat -> vaa'at. It can also be used in the place of a vowel, even though it does not change the pronunciation in this case. For example, here it's used to mark an omitted -i: päiväsi > päiväs', soisi > sois'.

I am looking at that phrase "Olei aikeissa soittaa sinulle."

Is the first word some kind of dialect or a mistake? Maybe it should be "olin"? I guess the meaning would have been "I was just thinking of calling you"?

I think it's a typo of olen or oli, although it reminds me of the Southwestern dialects where they form the past tense of some verbs without assimilating -e- to -i-, e.g. standard Finnish miettiä > mietin, dialectal miettiä > mietein. However, AFAIK olla is not one of these verbs.

(It is also strange to me that aikeissa is in the plural, but I guess that's just the way it is

Yeah, it's just a fixed expression.

[Woods]

maukua

indikatiivi: minä mau'un, minä mau'uin, mau'utaan/ei mau'uta, on mau'uttu / ei ole mau'uttu

imperatiivi: (sinä) mau'u!

What are these apostrophes for?

They show where the syllable break is. It matters because it affects the pronunciation. I'm not sure how to best describe it or if my attempt is even correct, but when I think of how I say these words, there's a small pause (perhaps even a short glottal stop) or a light secondary stress after the apostrophe.

Separating the vowels with an apostrophe also helps keeping the word more similar to its basic form, which makes reading and recognising it easier. The apostrophe is always put in the place of lost consonant: maukua -> *maukun -> mau'un; vaaka -> *vaakat -> vaa'at. It can also be used in the place of a vowel, even though it does not change the pronunciation in this case. For example, here it's used to mark an omitted -i: päiväsi > päiväs', soisi > sois'.

But with consonants it's official language, while with vowels it's some random (or in this case not so random) person's whim?

[Naava]

With consonants, it's standard spelling. Notice though that it's only used if the basic form has a long vowel or a diphthong in the first syllable and the next syllable has the same vowel. For example:
maku ('taste, flavour') > no diphthong/long vowel > maun, not ma'un
häkä ('carbon monoxide') > no diphthong or long vowel > hään, not hä'än
ruoka ('food') > has a diphthong uo, but the next syllable is not O > ruoan or ruuan, not ruo'an or ruu'an.
tiuku ('jingle bell') > has both a diphthong and the same vowel in the second syllable > tiu'un, not tiuun.

With omitted vowels, it's poetic/older style. (For example, I was still taught in school to write yht'äkkiä while nowadays the recommended spelling is yhtäkkiä.) It's also quite often used when writing in a dialect if two words have become merged.