Translation:The rice is hot.
I too miss a proper explanation of the particles, so I've had to look around online to understand what's going on. All of this comes from different websites, so I definitely recommend that you have a look at the links at the end. All credit goes to the rightful owners.
All right, let's dive into the wonderful world of grammar.
In the case of this sentence, が is used to describe the meal with an adjective (hot). Here is a quick summary of は vs が:
Marks the topic of a sentence (more on this later).
Contrast one option against another.
Used when elaborating on things already known to the listener.
Marks the subject of a verb (I prefer the word 'identifier', read below).
Seperates/calls out one option or thing from another.
Used when adding new information to the conversation.
Used when describing specific things with adjectives.
Marks object of potential-form verbs (can/able to).
Connects clauses with a meaning of "but" or "despite".
Now for a more detailed description of the difference between は and が：
I prefer to think about は as connected to the topic and が as an identifier (not as a subject particle as it is described on Duolingo). The reason for this is that "topic" and "subject" easily become very blurry and difficult to grasp for English speakers. We never have to distiguish between the two.
Take a look at this conversation to see how はdetermines the topic:
Alice: Today is the exam.
Bob: What about John?
Alice: John is tomorrow. (As for John, the exam is tomorrow.)
Once は has assigned "the exam" as the topic of their conversation, the exam does not need to be repeated when Bob asks about John's exam, nor when Alice replies. It kind of comes with the は.
Now think about が as an identifier, we are trying to identify a person without knowing who it is.
Bob: Who is the one that is a student?
Alice: John is the one who is a student.
If we were to use は in Bob's question, it would mean something like "Is who the student?".
So basically, wa and ga answer different (spoken or unspoken) questions:
(Q: Who are you?) A: 私はジョンです I am John
(Q: Who is John?) A: 私がジョンです Out of these people, I am the one who is John
(Q: What do you do?) 私は学生。 I am a student.
(Q: Who is the student?) 私が学生。 Out of these people, I am the one who is a student.
(Q: What do you think of Japan?) A: 日本は面白いです Japan is interesting
Q: Which country is interesting? A: 日本が面白いです Out of these countries, Japan is the country that is interesting
This is a very simplified way of distiguishing between は and が. Have a look at the sources below to see that the particles serve other purposes in a sentence.
I am still learning so I don't expect to be entirely correct and someone is more than welcome to tell me I'm entirely wrong and correct me, but the way I've been determining whether to use は or が, I haven't been wrong yet. As a side note, I've been using IME which means I have to type what I want to say rather than using preset words given by Duolingo. So in this case, rice will be established as the topic, the は of the conversation beforehand. So now it becomes the subject of the discussion, the が of the conversation (until the topic changes by use of は). I think it would go something like
ごはんはあついですか？ (Is the rice hot?)
はい、[ごはんが]あついです。(Yes, it [the rice] is hot.)
I think this depends on context and intonation.
For example, the way you would know if i was disscussing records or if i wanted you to record something. You can tell which i mean when i write the sentence out by using context clues.
In english when we speak we put emphasis on the start of the word for nouns and at the end for words.
"Let's go check out the music RECords"
"Can you reCORD that t.v. show for me."
I can't give you good Japanese examples but the concept is the same.
The way it was explained to us in another thread was that you can't say, "ごはんはあついです" because not all rice is hot. Rice can be cold too. If you said it with は, it would mean that Rice in general is a hot thing. If you use が, then you're saying that this particular rice is hot.
So you could use ごはんは if you were going to say that rice is white, or rice is cylindrical or something about rice in general; and you would say ごはんが if you want to say that it was cooked by grandma, or that it has teriyaki sauce, or something about a specific bunch of rice.
One way I saw は and が contrasted was that は emphasizes the object/verb while が emphasizes the subject.
For example, 「私はジョンです。」, is emphasizing that John is your name; however, if you say 「私がジョンです。」, it would be more like saying "No, I'm John.", since the emphasis is on the subject (you).
Here is the link to a particle cheat sheet I got this information from: https://www.tofugu.com/japanese/japanese-particles-cheatsheet/
I am Japanese . You know difficult kanji . Cool ! Excuse me . This Kanji ' 暑い ' is mainly used for the weather . For example , today is hot . 今日は暑いです。in this case , because it is food we use this Kanji ' 熱い ' . I am encouraged by your efforts ! English is difficult for me ! f(^_^) Is my English correct ? Bye .
When did we learn that gohan is a blanket term but also its own word for rice? They kinda just go from using it to say rice and meal and you kinda need to find the context yourself, even though it all has to do with food? It's kind of annoying.. I wouldn't mind knowing the difference if it went through that before. I wish there were better hints/notes for that in these lessons.
「ごはんがあついです。」 or "The rice is hot." is saying that some particular rice in context has the property of being hot. 「あついごはんはあります。」 or "There is hot rice." is asserting the existence of rice that is hot. The former is about some rice the speakers are both already aware of. The latter is pointing out the existence of hot rice that the listener presumably wasn't aware of.