"I do not want green pants."
The simple answer is that は is a topic marker and が is a subject marker. Usually, in these cases, the topic is implied to be "I"/"me", and the thing being wanted or liked is marked as the subject. However, it's possible to simply use a topic marker for the thing being wanted/liked instead.
Both replies are somewhat incorrect - hoshii is the self-contained form, which you use for adjectives, hoshiku is the continuative form, which is used to connect it to following words. This can be an adverb if a verb follows, or a negation if negation follows (nai). Japanese doesn't really care about distinguishing adverb/adjective, the change in form reflects its relation to other words in the sentence than its technical usage. The same thing happens with tte form verbs that will be encountered later.
The continuative form 連用形is also called adverbial form because it avts exactly like an adverb in the case of adjectives.
The true negative form for ほしい is ほしからず which is not really used any more in modern Japanese. Instead the negative form is made up of ほしく(adverbial form of adjective) + ない(adjective). So in this negative case, declaring ほしく as an adjective is not wrong.
I'm 100% certain Keith meant to write it exactly how he did. ^^
欲しがらず wouldn't make sense in relation to his post.
欲しからず fits with what he was saying.
If you're curious why I'd say this, you might be interested in checking out the following excellent discussion threads Keith posted a while back. I've only glanced through them in the past, but I imagine he must have included the negative versions of adjectives there:
I went through the whole post and didn't see anything related to ほしからず, which the 予測変換「よ・そく・へん・かん」 on my Japanese input didn't pickup the kanji for.
The thread was more about classical Japanese which I think is more of an N1 topic. Anyways, if we need classical Japanese to explain the grammar in these Duo's lessons, then it's way over the head of a beginning learner.
Maybe the true negative form is ほしかる、ほしからず and isn't used in modern Japanese anymore. I'm not even sure what he means by true negative form for 欲しい
@Alan946894, yes, this is a topic with classical Japanese. 欲し as a シク adjective - irrealis form ほしから + negative auxiliary verb ず. It does not come up with my 予測変換 also. We don't really need classical grammar to explain. For beginners, understanding adjectives have a different conjugation family as compared with verbs, is all we need to know.
Hi Alan, I forgot why I studied into classical Japanese at the beginning. However when we look at the questions asked by Japanese learners, there are quite some chances that the answer is related to classic Japanese. e.g. this simple question: Why is は read as わ when it is a particle.
I have pretty much finished learning the modern Japanese as I am fluent enough. I find that classical Japanese helps a lot in deepening knowledge in the modern Japanese. I am always excited whenever I find a link between modern and classical, maybe that is what makes me continue looking for more in the classical space and continue learning Japanese.
In watching recent Japanese TV shows I have seen instances where パンツ specifically meant underwear. I have never seen it used to refer to trousers or pants. (and yes @AnaLydiate I am an American and I use the word trousers, but then I also use latrine and other words which are common military terms).
No, it can mean both. A story of mine: A few years ago I used the laundry service in a hotel. There were options ズボン and パンツ in the order sheet. I wanted to wash my denim jeans and I checked ズボン. The hotel service replied me that it was not ズボン and should be パンツ. ズボン is for those trousers that come with the business suit.
I think ズボン and パンツ in a broader sense means all kinds of trousers. パンツ can also mean underwear. Pronunciation is different: trousers is PANTSU and underwear is Pantsu (caps for HIGH tone and small letters for low tone)
I am not an expert of fashion so I struggle all the times in understanding these different type of names :-)