Description:

The modifier 'la' is a modifier of polarity that reinforces or emphasizes the positivity of the verb it is applied to when used as a verb modifier, often in contrast to a negative assertation. It can also be used as a noun modifier, where it serves as a quantifier. In the verbal sense it can also be used as an interjection. It means 'yes' or 'some' or 'does'. See also the related negative modifier of polarity, 'ikky', attached.

Verb Modifier (Adverbial):

La is restricted as to where it can go in the sentence, unlike other verb modifiers. It must appear in the verb phrase as the last modifier before any modifying chained verbs. It asserts the affirmative meaning of the overall verb phrase. It cannot move, but it can be mirrored with another polarity particle, either ikky or la, at the beginning of the sentence to answer a yes/no question.

Interjection (Answer 'Yes' to Yes/No Question):

As a word for 'yes' to answer a yes/no question, la can be used on its own, or with a sentence that clarifies the answer. If there is a clarifying sentence, grammatically it must also have a particle of polarity, positive or negative, associated with the verb. Examples:

La, a costo se la an uzre.
Yes, the house is green.

La, a costo se ikky an uzre.
Yes, the house is not green.

The first of the examples, where a positive meaning is emphasised, requires the second la on the verb to be considered grammatical. However, in less careful speech, it is sometimes ommitted.

Tag Question:

Ikky and la  both can appear at the end of a sentence to turn it into a question. In this case, the particle is not usually echoed inside  the verb phrase, although it can be:

A costo se an uzre, ikky?
The house is green, no?

A costo se an uzre, la?
The house is green, yes?

Noun Modifier (Quantifier):

When used with a noun, la is a member of the quantifier class and means the same thing as 'some' as in 'Some cats are black'. It asserts that at least one member of the class exists. For example:

Jar la paluh te slek az skitrem.
The-ERG-PAUC some dog hit-NP-IMP eat the-ABS-PL mouse.

'Some dogs eat mice.'

Note that la asserts no more than a few or a subset of all potential members of the class, and therefore demands that the article agree with it by being in the paucal number. Logically the singular or plural would be possible, but the idiomatic expression is the paucal, mirroring the expression using ikky. Also note that the 'la' is not at all strictly necessary to convey this idea and could be omitted, but its use adds precision and emphasis to the statement.

Tight Binding Form:

La has a regular tight binding form used to modify other modifiers, 'lano'. It is a member of the 'polarity set' of core tight binding modifiers, along with 'ik', the tight binding counterpart of 'ikky'. It means 'definitely' or 'surely' as a tight binding modifier.

Mathematics:

In math, 'lano' is used as the particle to denote a positive number, if required for clarity or emphasis.