how to convert adj to adverbs properly?

[jpd1]

hello everyone!

i understand that to convert an adj (adjective) to an adverb you need to do the following:

if it is an i adj then you take the i off and put ku instead.

like: yoi = yoku

and if it's a na adj then you make the na into ni

like: kirei na = kirei ni

that's how a certain book explains.
but i have a problem with this explanation.

1. first of all, how do you convert the adj yukuri ? yukuruku? i don't think so.
also i don't think it is a na adj, so yukuri ni (from yukuri na) doesn't sounds right either.

2. another problem with the adj zettai. (zettai = definite)
i heard all too often the adverb zettai ni (definitely).
but i can't say i heard zettai na (the actual form of zettai , right?) at all... (is it really a na adj? if so, why it is never used as zettai na?)

3. and to sum it up, how do you say: "walked slowly" in Japanese?
yukuri arukimashta is probably what most of us think but according to the book explanation and my understanding it is actually a mistake.
because yukuri describes arukimashta "the walking" so it is definitely an adverb.

please correct me on any of my mistakes here (especially if there are any in my "explanations").
thank you very very much!

[Psy]

hello everyone!
1. first of all, how do you convert the adj yukuri ? yukuruku? i don't think so.
also i don't think it is a na adj, so yukuri ni (from yukuri na) doesn't sounds right either.

yukkuri is an adverb on its own without attaching any particles. Thus, there is no yukkuri ni or yukkuri na.

2. another problem with the adj zettai. (zettai = definite)
i heard all too often the adverb zettai ni (definitely).
but i can't say i heard zettai na (the actual form of zettai , right?) at all... (is it really a na adj? if so, why it is never used as zettai na?)

zettai is actually a no adjective (e.g. behaves just like a noun), so when you join it with another word it's zettai no. byouki is another example of this.

3. and to sum it up, how do you say: "walked slowly" in Japanese?
yukuri arukimashta is probably what most of us think but according to the book explanation and my understanding it is actually a mistake.
because yukuri describes arukimashta "the walking" so it is definitely an adverb.

yukkuri arukimashita is correct since, once again, yukkuri is an adverb on its own.

Hope that clarifies things!

[Bueller_007]

Zettai-no is more common, but zettai-na is also correct. It can also be used adverbially by itself, without ni.