掲示板 Forums - い/な adjectives difference

First, check on your spelling. This is important. The words you're trying to use is spelled 大きい and 小さい*. Both of these are い-adjectives.

Second, it's really easy. As I said above, check the spelling. That already tells you what it is right away.

Now, the breakdown on spellings: い-adjectives are just that. It's virtually every adjective that ends with the okurigana, い, except 2 - きれい and 嫌い (because everyone hates exceptions). These are actually な-adjectives. That's it!

な-adjectives are basically everything else. Even words that are only in kanji!

There's also a third classification, the irregular adjective, which is basically only 1: いい. That sounds confusing, right? It sounds like I should have mentioned this earlier, but believe me, it's not.

The reason いい isn't an い-adjective, and neither a な-adjective, is because it's the only word that sets it apart from the two. When it's conjugated, instead of messing with the last vowel, the whole word changes. It's actually a modern version of 良い (よい). So everything is based on the form of that word, rather than いい. Don't ask why. Memorize.

*EDIT: I had assumed you meant 大きい and 小さい.

The tricky thing particularly with な-adjectives as opposed to い-adjectives is that you must attach the な when you're describing a noun. い-adjectives do not use な.

大きな・小さな are only used as direct modifiers before nouns.

大きな声

声が大きだ

手を大きに広げる

大きい・小さい can be used before nouns, after nouns or as adverbs before verbs.

大きい声

声が大きい

手を大きく広げる

When used in front of a noun, they are interchangeable. For all the rest you have to use the i-adjective version for these two.

​I was going to make a comment about that (which is why I initially pivoted to the い-adjectives per the question). I just couldn't really figure how to word it yet. I opted for the basic part of the question rather than getting into the example マイロー was leading to. It's also something that I haven't yet studied, so this is taking me a bit to understand it.

So, I can say this is more of a slightly advanced concept for beginners although people are already exposed to such adjectives in their vocabulary. こそあど demonstratives also fit in this classification. Following that, there are some words that also don't have the "な" ending in them, such as る, の, た, が, etc., which may make it difficult to spot the difference.

In dictionaries, な-adjectives may be noted in words by saying "word(な)", which is just a way of saying that な is used in times kind of like a particle when that word is attached to a noun. As a 連体詞, 大きな, for example doesn't fall into the な adjective classification as dictionaries wouldn't say "大きな(な)" or "大き(な)" for that word. "大き(な)" and "大きな" are two separate words, just to clear things up. So 大きな(な) does not exist. So, 連体詞 basically are used more like an い-adjective.

And so one other thing I know is that the main difference with 連体詞 and な-adjectives is that 連体詞 words cannot be conjugated.

As someone who is a beginner, this is a subject that I have yet to be taught. It being a different classification is a mutually exclusive matter. I do not see where I even said they were in the same classification.

​I said that for the OP who was asking how to tell the difference between adjectives, just to keep the whole thing simple. It wasn't about its definition.

​Again, where did I mix the two? The only point of confusion is when you generalize な-adjectives since they're not adjectives which end with the い okurigana except the two words, one might think that some adjectival words are な-adjectives. So, one difference to that is the fact they aren't words that conjugate, which would make it 連体詞, which is all I said about that.