... Stupid question, but, how do I know if it's a Na or I adjective?
Knowing how the words are written with kanji is what gives away whether it is an い or な adjective. Does it end in anything other than い ? Then it's な e.g. 好き/すき No kana after the kanji ? Then it's な e.g. 綺麗/きれい Is the adjective just the stem of a verb ending in う ? Then it's な e.g. 嫌い/きらい (see 嫌う) Otherwise it's い e.g. 甘い/あまい
If in doubt you can always check the dictionary here, which will tell you what kind of adjective it is.
If you don't have a dictionary, and you don't know how the words are written in kanji, then your best bet is to guess that adjectives that end in い are い adjectives and the rest are な adjectives.
Think of the て(で) form as glue: it only comes when you are gluing two similar things (adjective + adjective) together. It is not necessary when putting an adjective next to a noun.
I have a doubt that when does な is placed after adjective. For Example : この神社は本当に有名なところです。 東京はとても賑やかな都市です。 So here are you can see, why is there -na placed, even thought without -na, it would still mean the same.
There is a deeper technical reason (probably because the adjectives without な are closer to being nouns), but even if the "meaning" is the same, there are still grammatical rules that need to be followed :)
There is a deeper technical reason (probably because the adjectives without な are closer to being nouns), but even if the "meaning" is the same, there are still grammatical rules that need to be followed :)
