Adverbs

The language would likely adopt all single-form adverbs such as mox (soon), numquam (never), semper (always), iam (already), non (not), ibi (there), hic (here), igitur (therefor), and the like.

Forming adverbs from adjectives, however, can be a complicated endeavor. In Latin, first and second declension adjectives (which in this language would end in an -a) would be formed by changing the ending to an -e (longa -> longe meaning far). But third declension adjectives (which in this language would end in -e) would be formed by adding -iter as an ending (grave -> graviter meaning heavily).

My goal is to reduce grammatical complexity while maintaining lexical root diversity. In the case of adverbs from adjectives, there is one lexical root and the grammatical division may be an additional headache. I'd prefer one simple rule.

That rule could be to change the ending to an -e in all cases. Of course this would make adverbs like longe (far), but adjectives ending with -e would simply not change. I personally don't think that's a major problem though. Many languages don't have adverbs and get by on adjectives alone. Take the example below:

Latin: Nos egimus audacter - We acted bravely. In this language, for simplicity, the only form available would be audace. So the following: Nos egi audace - "We acted brave." In english there's a difference there, but there need not be one in this language.

Also: me ivi ibi felice "I went there happy" is close enough to "I went there happily."

So in this language, it will be sufficient to use the adjective form to try to express an adverbial concept. If the adjective ends in an -a, I suppose it would be possible to change the ending to an -e if the user would like to specify, but it shouldn't be otherwise necessary. Also, I suppose there could be an optional rule to add -mente or -modo to suggest the word is used as an adverb, but only when necessary! I would continue to maintain a hyphenated word, so the roots are apparent. The use of -mente is the development we see in romance languages such as French and Spanish.

felice-mente (with a happy mind, happily)

felice-modo (in a happy way, happily)

libera-mente (with a free mind, freely)

libera-modo (in a free way, freely)

I don't think it would be a harm maintaining one irregular adverb such as bene (well) but bona (good) could also work.

Te feci bene - you did well.

Te feci bona - you did good - acceptable

The rule could be bona -> bene instead of bone.