Учитель только что ответил мне в чате, и теперь всё понятно.

Только что means just now or a moment ago.

So:

• Учитель только что ответил мне = The teacher just replied to me

It is a very common Russian expression for something that happened very recently.

Examples:

• Я только что пришёл. = I just arrived.
• Она только что позвонила. = She just called.

Ответил is the perfective past form of ответить, which focuses on a completed result: the teacher gave a reply.

In this sentence, that is exactly the point: the teacher has now replied, and because of that, everything is clear.

• ответил = replied / gave an answer
• отвечал = was answering / used to answer / answered in a process-oriented way

Here, Russian prefers ответил because the action is seen as a finished event with a result.

Compare:

• Учитель ответил мне. = The teacher replied to me.
• Учитель отвечал мне весь вечер. = The teacher was answering me all evening.

Because the verb ответить / отвечать takes the person answered in the dative case, with no preposition.

So:

• ответил мне = replied to me
• ответил ему = replied to him
• ответила нам = replied to us

This is just how the verb works in Russian.

A useful pattern:

• кто-то ответил кому-то = someone replied to someone

So in your sentence:

• Учитель ответил мне = The teacher replied to me

В чате means in the chat.

The noun чат here is used with в + prepositional case to show location or the place where the communication happened.

• чат → в чате

Examples:

• Я написал ему в чате. = I wrote to him in the chat.
• Мы обсуждали это в чате. = We discussed it in the chat.

For many English speakers, this is worth noticing because English often says in the chat too, but sometimes learners wonder whether Russian might use a different preposition. Here, в is the normal choice.

Because this sentence joins two clauses:

1. Учитель только что ответил мне в чате
2. теперь всё понятно

These are two separate predicative parts, so Russian normally puts a comma before и.

Even though English sometimes feels lighter about commas, Russian punctuation is often stricter in compound sentences.

So:

• ..., и теперь всё понятно. = ..., and now everything is clear.

Теперь means now in the sense of now as a result of what happened before.

That fits this sentence well:

• The teacher replied.
• Now everything is clear.

So теперь connects the present situation to the new information.

Сейчас can also mean now, but it often points more to the present moment in a more direct time sense.

Very roughly:

• теперь = now, from this point on / now as things stand
• сейчас = now, right now

In this sentence, теперь is the more natural choice.

Because понятно here is not a normal adjective modifying a noun. It is used as a predicative word meaning:

• it is clear
• understandable

So:

• всё понятно = everything is clear / everything is understandable

By contrast, понятное would be an adjective form attached to a noun:

• понятное объяснение = a clear explanation
• понятное слово = an understandable word

In your sentence, Russian is making a statement about the situation, not describing a noun directly.

This is a very common Russian pattern. Words like понятно, интересно, важно, трудно, легко are often used in an impersonal predicative way.

So:

• Мне понятно. = It is clear to me.
• Нам интересно. = It is interesting to us.
• Здесь трудно работать. = It is hard to work here.

In всё понятно, понятно functions as this kind of predicative word, not as a regular adjective agreeing with a noun in the usual way.

Even though всё means everything, the structure is basically:

• Everything is clear not
• all clear things

Всё means everything.

It is different from все, which usually means all or everyone, depending on context.

• всё понятно = everything is clear
• все понятно is usually just an informal spelling of всё понятно, because Russian often omits the dots over ё in everyday writing

Important point:

• In real Russian texts, you will very often see все понятно
• But the intended meaning is still often всё понятно

Learners should know both:

• всё = everything
• все = all / everyone
  but in ordinary writing, ё is frequently written as е

Yes, absolutely.

You can say:

• Учитель только что ответил мне в чате, и теперь всё понятно.
• Учитель только что ответил мне в чате, и теперь мне всё понятно.

Both are natural.

The version without the second мне is fine because it is already obvious who understands now. Russian often omits words that are clear from context.

Adding мне makes it a little more explicit:

• теперь мне всё понятно = now everything is clear to me

Russian word order is flexible, but this version sounds natural and neutral.

• Учитель только что ответил мне в чате, и теперь всё понятно.

Why this order works well:

• Учитель introduces the subject first
• только что naturally goes before the verb
• ответил мне keeps the verb and its indirect object together
• в чате comes after that as the place/context
• теперь smoothly introduces the result in the second clause

You could change the order a bit, but the emphasis would shift. For example:

• Только что учитель ответил мне в чате...
  This puts more emphasis on just now.

• Учитель ответил мне только что...
  Also possible, but a little different in rhythm and focus.

So the given order is a very standard, natural one.

The past-tense verb would change to match the teacher’s gender.

• Учитель только что ответил мне... = if the teacher is male
• Учительница только что ответила мне... = if the teacher is female

You could also say:

• Преподаватель ответил... = male teacher/instructor
• Преподавательница ответила... = female teacher/instructor

In the original sentence, ответил tells you the speaker is talking about a male teacher, unless учитель is being used generically in some special context.

No. Учитель is a normal word for school teacher, especially in a general sense.

Depending on context, Russian might also use:

• преподаватель = teacher/instructor, often for higher education or more formal contexts
• учительница = female school teacher
• преподавательница = female instructor/teacher

So the sentence could be adapted depending on who the person is.

But grammatically, the original sentence is completely natural:

• Учитель только что ответил мне в чате, и теперь всё понятно.

Yes, but learners should be careful with English usage.

Russian ответить кому-то is often best translated as:

• reply to someone
• answer someone

So:

• ответил мне can be answered me or replied to me

In natural English, replied to me in the chat often sounds especially good here.

The Russian structure is straightforward:

• ответил = replied / answered
• мне = to me
• в чате = in the chat

So yes, the grammar maps quite closely, even if English style may prefer replied to me.