Questions with a yes/no response in toki pona have a special grammatical structure. The word in question is repeated twice with ala in between. The repeated word is generally constrained to the [action/quality/state of being] or a pre-verb, even if that word is also acting in another capacity such as a preposition.
- sina pali ala pali? - [subj][action] ala [action]? - are you working?
- soweli li tan ala tan kasi suli? - [subj] li [action/prep-head] ala [action/prep-head][prep-obj]? - Did the animal come from the woods?
- moku li suwi ala suwi - [subj] li [quality] ala [quality]? - Is the food tasty?
To answer, the target word is repeated by itself to answer yes, or with ala for no.
- pali. - Yes (I am working).
- tan ala. - No (not from the woods).
- suwi. - Yes (it’s good tasting).
I say above generally constrained. In pu the structure is described solely with the word acting as the verb, but this is also before pre-verbs are introduced. jan Pije and jan Lantan do not describe any limitations to it’s use. My impression is if there is a pre-verb this is often the preferable word to target:
- sina wile ala wile moku - Do you [want/ not want] to eat?
- sina wile moku ala moku - Do you want to [eat/not eat]?
The later makes one option appear to be “Do you want to not eat?” rather than “Don’t you want to eat?”
yes / no questions
Just as in Chinese, toki pona has the verb-not-verb structure for yes/no questions. Most of the time ala used in this way will behave normally.
The only thing new here is the question mark glyph block is used instead of a period.
questions in the four-block structure
However, if you create a four block structure with the subject-verb-ala-verb, there is an exception to our block order rules:
The four block are grouped in what would really be a clockwise arrangement.
The reason for this is to avoid doubling the same verb glyph next to itself. This way they remain separated by ala.
Think of the entire group as one single block with the subject and ala in two opposite corners, and the repeated verb in the other two corners. The ‘X’ shape in the middle of ala echoes this structure.