The verb ‹bos› ‘to be/being’ is the most complex verb in the Cornish language. It has more tenses and moods than most other Cornish verbs (present, present-future, imperfect, habitual imperfect, conditional, present-future subjunctive, imperfect subjunctive, and imperative).
Now, in addition, the present and imperfect have two different sets of forms per person, the so-called “short form“ and “long form” - sometimes also called “descriptive” and “locative”, and they are used in different situations. For the explanation I’ll just stick to the 1st person singular, “I“:
basic short form/descriptive
ov ‘I am’
basic long form/locative
esov ‘I am’
The short form/descriptive is used to describe what/who something/-one is like, e.g.:
yth ov vy skwith ‘I’m tired’
The long form/locative is used to express where something is, e.g.:
yth esov vy omma ‘I’m here’
To ask the question, you drop the statement-particle ‹yth› and would replace it with the question-particle ‹a›, but since these tenses start with a vowel, the question particle drops:
Ov vy skwith? ‘Am I tired?’
Esov vy omma? ‘Am I here?’
The negation is formed with the negative particle ‹nyns›:
Nyns ov vy skwith. ‘I’m not tired’
Nyns esov vy omma. ‘I’m not here.’
The form **eson vy doesn’t exist, you probably mean ‹esen vy› - this is the long/locative imperfect: ‹yth esen vy omma› “I’ve been here (for an extended period of time until the present)”.
To stress, or emphasise, that you are tired, or when answering the question “How do you feel?” - you want to place ‹skwith› ‘tired’ at the beginning of the sentence: ‹Skwith ov.› “I’m tired(!!!)” - Cornish expresses emphasis by word order, the more important the information contained in a word is, the further front in the sentence it ‘wants’ to go. English does this by tone alone.
Now, if you want to stress that it is “I” who is tired, you have to move “I” to the front of the sentence… simple enough, but why does the verb form change from ‹ov› to ‹yw›? When you put the pronoun before the verb, you are essentially making a relative clause, that means you are saying something like “(It is) I (who) is tired”, and this is why (in Cornish) ‹ov› ‘am’ changes to ‹yw› ‘is’ (3rd person singular). ‹My yw skwith› would be the answer to the question “Who is tired?”
In such sentences where the subject is stressed, the verb form is always in the 3rd person singular, for all persons and numbers (e.g. ‹Ni yw skwith› ‘We(!!!) are tired’, ‹An fleghes yw skwith› ‘The children(!!!) are tired’).
To express ‘I’m tired’ neutrally you say: ‹Yth ov skwith.› ‘I’m tired’. You can add ‹my› > ‹vy› for clarity and a little emphasis on “I”: ‹Yth ov vy skwith.› ‘I’m(!) tired’.
The long form works a little differently, so stick to the syntax ‹yth esov vy omma› for now, until you delve deeper into the forms (it has different relative and definite/indefinite forms).
The long form is also used to make the continuous form:
‹Yth esov vy ow mos tre.› “I’m going home.”
‹Yth esov vy ow tyski Kernowek.› “I’m learning Cornish.”
