Hmmm...I'm not 100%, but my bet would be on the latter, as I've seen it written as both 'ó, mo léan' and as simply 'mo léan'. Also, the phrase doesn't make much sense when the ó is seen as a preposition, but as we both know, when it comes to Irish, that doesn't necessarily mean anything. :p
The basic structure of a sentence in English is "subject-verb-object". The verb is "eats", the subject (the thing/person doing the verb) is "the cat" and the object (the thing being eaten) is "the spider".
You can tell that it's the cat eating the spider because the subject comes before the object.
The structure of a sentence in Irish is "verb-subject-object" - itheann is the verb, an cat is still the subject and an damhán alla is the object. You can tell that it's an cat eating an damhán alla because the subject comes before the object.
No, because when you go beyond the basics, it's actually predicate-subject-object, but for most verbs, the verb is the predicate of the sentence, so predicate-subject-object is actually verb-subject object . But not the copula. With the copula, instead of a predicate verb, you have a predicate noun, and the predicate still comes before the subject, but it is now copula-predicate-subject.
itheann an cat an damhán alla - "the cat eats the spider"
itheann cat an damhán alla - "a cat eats the spider"
itheann an cat damhán alla - "the cat eats a spider"
itheann cat damhán alla - "a cat eats a spider"
cat - "(a) cat"
an cat - "the cat"
damhán alla - "(a) spider"
an damhán alla - "the spider"