"Is it cold today?"
さむい さむく i cant figure out the differnce from the context of these sentenses
From my admittedly limited knowledge,さむく for the negative conjugation and for adverbial usage.
The ない (nai) ending make the first word negitive, and the ですか (desuka) is asking a question, so さむくないですか (samukunaidesuka) translates to something like "is it not cold?"
Why do I have to use は when I write 今日, but in the one before I wrote よる雨がふります without any は after よる?
The は is used to emphasise that you are talking about today specifically. It would translate more as "As for today, is it cold/hot?" は is often used for a little more emphasis and as a topic marker. Particles are difficult to get a hang on, you'll get there! :)
But there is no requirement for having は, and what if you're emphasizing that it's cold?
In general I use a particle for time if available. Duo seems fairly inconsistent on requiring them. Often the distinction between using it or not is not discernable in the English translation and using a particle for time (when you can) doesn't ever seem to be marked as incorrect.
I know this is a late response, but for anyone wondering: 寒い (さむい) is used for the weather (or sometimes as slang to indicate that something is boring or lame). 冷たい (つめたい) is used for objects that you can touch (or to describe someone's personality as cold).
how to type in japanese when duo dont provide the keyboard for it :< i can type in romaji but not accepted