Learn Hardcore Indonesian: Guru mengirim materi melalui email. - The teacher sends the material via email.

Indonesian does not use articles like a/an or the.
The word guru by itself can mean a teacher, the teacher, or even teachers (plural), depending on context.

Guru mengirim materi melalui email.
→ could be A teacher sends the materials by email or The teacher sends the materials by email.

If you really want to make it clearly that specific teacher, you might use context, a name, or something like:

Guru itu mengirim materi melalui email. = That/that specific teacher sends the materials via email.

Why does mengirim cover “sends”, “is sending”, and “sent”? How do tenses work here?

Indonesian verbs do not change form for tense (past, present, future).
The verb mengirim simply means to send / sending, and the time is understood from context or from time words like kemarin (yesterday), sekarang (now), nanti (later), besok (tomorrow), etc.

So:

Guru mengirim materi melalui email.
- could be The teacher sends the materials via email.
- or The teacher is sending the materials via email.
- or The teacher sent the materials via email.

If you really need to show future, you can add akan:

Guru akan mengirim materi melalui email. = The teacher will send the materials via email.

What is the base form of mengirim, and what does the prefix me- do?

The base form (root) is kirim, which means send.
The verb mengirim is formed from me- + kirim, with a spelling change (k disappears, becoming mengirim).

Prefix me- (often written as meN- in grammar books) usually:

turns a root into an active verb:
- kirim → mengirim (to send)
- baca → membaca (to read)
- tulis → menulis (to write)

So mengirim is the normal active form meaning to send / sends / is sending / sent.

What’s the difference between mengirim and mengirimkan?

Both are correct and very common, and often they can be translated the same in English.

mengirim materi = mengirimkan materi
Both: to send the materials

Some nuances (not strict rules):

mengirim is a bit more neutral and slightly simpler.
mengirimkan can feel a bit more complete or polite/formal, and can put a tiny bit more focus on the recipient or the act of delivering.

In this sentence, both are fine:

Guru mengirim materi melalui email.
Guru mengirimkan materi melalui email.

For a learner, you can safely treat them as interchangeable most of the time.

What exactly does materi mean here? Why does it translate as “materials” (plural)?

The word materi (from English material) often means learning/teaching materials, content, or material in an abstract sense.
Indonesian usually does not mark plural with an ending like -s. One word can be singular or plural depending on context.

Here, materi is naturally understood as teaching materials, which in English is usually plural:

Guru mengirim materi melalui email.
→ The teacher sends the (teaching) materials via email.

If you want to be clearer that it’s study material, you can say:

materi pelajaran = lesson material(s)
materi ujian = exam material(s)

Is the word order the same as English? Can I move the words around?

The basic word order here is Subject – Verb – Object – (extra info), which matches English:

Guru (S) mengirim (V) materi (O) melalui email (extra)

This is the most natural and clear order. You should not move the object in between the verb and melalui like:

✗ Guru mengirim melalui email materi. (sounds wrong/unnatural)

The normal pattern is:

Subject + Verb + Object + [prepositional phrase]
→ Guru mengirim materi melalui email.

You can sometimes move the time expression, for example:

Besok guru mengirim materi melalui email. (Tomorrow the teacher sends the materials via email.)
Guru besok mengirim materi melalui email. (also acceptable in speech)

Why is melalui used? Could I use dengan, lewat, or pakai instead?

Melalui means through / via and is quite neutral and standard, especially in writing.

In everyday Indonesian, you might also hear:

lewat email = via email (more casual)
dengan email = with/by email (okay, but a bit less exact)
pakai email = using email (very conversational)

All of these are understandable:

Guru mengirim materi melalui email. (neutral / standard)
Guru mengirim materi lewat email. (very common in speech)
Guru mengirim materi pakai email. (casual)

For learning, melalui and lewat are the two most useful here.

Is email really used in Indonesian, or is there another word?

Yes, email is widely used in Indonesian, especially in everyday speech and writing.
You may also see:

e-mail (with a hyphen) – more formal/older style
imel – a more “Indonesian-ized” spelling, not as common these days
surel (from surat elektronik) – an official Indonesian term, but much less common in real life speech

In real usage, people usually say email:

Kirim saja lewat email. = Just send it via email.

How would I say “The teacher will send the materials via email tomorrow” in Indonesian?

You can add akan for future and besok for tomorrow:

Guru akan mengirim materi melalui email besok.

This clearly means: The teacher will send the materials via email tomorrow.

You can also move besok to the front:

Besok guru akan mengirim materi melalui email.

Both are natural. The verb mengirim itself doesn’t change; the time word and akan give the future meaning.

Can I drop guru or materi if they are already known from context?

Yes. Indonesian often omits words when the meaning is clear from context.

If everyone knows you are talking about the teacher, you might just say:

Mengirim materi melalui email.
= ([He/She/The teacher]) sends the materials via email.

If the thing being sent is obvious, you might drop materi:

Guru mengirim melalui email.
= The teacher sends (it/them) via email.

In careful, complete sentences (like in textbooks), you’ll usually see the full form, but in real conversations, subjects and objects are often omitted when understood.