Learn Hardcore Indonesian: Ilmuwan lain berbicara tentang iklim dan menjelaskan mengapa musim panas sekarang terasa lebih panas. - Another scientist talks about the climate and explains why summers now feel hotter.

Which one is meant depends on the context. In many contexts like your sentence, English would naturally choose “other scientists” because we tend to imagine more than one scientist talking, but Indonesian itself allows both readings.

If you really want to make it clearly plural, you could say:

para ilmuwan lain = (the) other scientists (explicitly plural, human) If you really want to make it clearly singular, you might add a number or a word like:
seorang ilmuwan lain = another scientist (one other scientist)

Why is “lain” after “ilmuwan” and not before it, like “lain ilmuwan”?

In Indonesian, most adjectives and adjective-like words come after the noun:

ilmuwan lain = other scientist(s)
buku baru = new book
rumah besar = big house

Putting “lain” before “ilmuwan” (“lain ilmuwan”) is not grammatical in standard Indonesian. So the order noun + lain is the normal one.

What is the difference between “ilmuwan lain”, “ilmuwan yang lain”, and “ilmuwan lainnya”?

All three involve the idea of “other scientists”, but the nuance is slightly different:

ilmuwan lain
- Neutral “other/different scientist(s)”.
- Often understood as “some other scientists” without a very strong sense of “the rest of a known group”.
ilmuwan yang lain
- More like “the other scientists” (the rest of a group already known in the context).
- The “yang” points to a specific, already-identified set: “those other ones”.
ilmuwan lainnya
- Similar to “ilmuwan yang lain” but a bit more compact.
- Often used like “the other scientists” / “the rest of the scientists”.

In your sentence, ilmuwan lain works well because the focus is just on “other scientists” in general, not necessarily “the remaining ones from a specific group”.

What does “berbicara tentang” mean? Is it the same as “talk about”?

Yes, “berbicara tentang” corresponds closely to “to talk about” or “to speak about”.

berbicara = to talk / speak
tentang = about / regarding

So:

berbicara tentang iklim = to talk about climate

You’ll also see related patterns:

berbicara soal iklim (often more informal; talk about climate)
membicarakan iklim (more formal, “discuss climate”, with membicarakan as the verb)

Is “tentang” always necessary after “berbicara” when I say “talk about X”?

Not always, but it’s very common and very natural.

Common options:

berbicara tentang iklim – talk about climate (standard, neutral)
berbicara soal iklim – talk about climate (slightly more casual, common in speech)
membicarakan iklim – discuss climate (more formal/literary)

If you remove the preposition altogether, you usually need a different verb shape, e.g. membicarakan instead of berbicara tentang.

So:

berbicara iklim ❌ sounds odd in standard Indonesian.
Use berbicara tentang iklim ✅ or membicarakan iklim ✅ instead.

Why is there no subject repeated before “menjelaskan”? Why not “dan ia menjelaskan …”?

In Indonesian, if two verbs share the same subject, you usually mention the subject only once, at the start, and then just connect the verbs with “dan”:

Ilmuwan lain berbicara tentang iklim dan menjelaskan …
= Other scientists talk about the climate and explain …

The subject “ilmuwan lain” is understood to apply to both verbs:

(ilmuwan lain) berbicara
(ilmuwan lain) menjelaskan

Adding “ia” (he/she) or “mereka” (they) in the second clause is possible but usually only done when you want extra emphasis or clarity, for example if the subject of the second verb might otherwise be confusing.

What is the function of “mengapa” here, and how is it different from “kenapa”?

In your sentence:

menjelaskan mengapa musim panas sekarang terasa lebih panas
= explain why summer now feels hotter.

“mengapa” is a formal/neutral word for “why”.
“kenapa” is very common in speech and informal writing, also meaning “why”.

In this sentence you could also say:

… dan menjelaskan kenapa musim panas sekarang terasa lebih panas.

Both are correct. “mengapa” just sounds a bit more formal or bookish, which fits well with a context involving scientists and explanations.

How does “musim panas sekarang terasa lebih panas” work grammatically? What is the structure?

Breakdown:

musim panas = summer (literally “hot season”)
sekarang = now / nowadays
terasa = feels / is felt (gives the sensation of)
lebih panas = hotter (more hot)

Structure:

[Subject] [Time word] [Stative verb] [Adjective]
musim panas sekarang terasa lebih panas
summer now feels hotter

So it’s like saying:

“Summer now feels hotter.”
or
“Summers nowadays feel hotter.”

What does “terasa” mean exactly, and how is it different from “merasa”?

Both come from the root rasa (feeling, sensation, taste), but they’re used differently:

terasa (with ter-)
- Means “to be felt / to feel (to someone)”.
- Describes how something seems or feels from the outside.
- Used with a thing or situation as the subject.
- Example:
  - Musim panas terasa lebih panas.
    = Summer feels hotter.
merasa (with me-)
- Means “to feel” in the sense of a person’s internal feeling (emotion or physical sensation).
- Used with a person as the subject.
- Example:
  - Saya merasa kedinginan.
    = I feel cold.

So:

musim panas terasa lebih panas ✅ (summer feels hotter)
saya merasa musim panas lebih panas ✅ (I feel that summer is hotter)

How does “lebih” work in “lebih panas”? Is that how you normally form comparatives like “hotter”?

Yes. In Indonesian, comparatives like “hotter / bigger / more interesting” are usually formed with lebih + adjective:

lebih panas = hotter / more hot
lebih besar = bigger
lebih menarik = more interesting
lebih mahal = more expensive

So the pattern is:

lebih + adjective = “more + adjective” / “-er”

For superlatives (“the hottest, the biggest”), you use paling:

paling panas = hottest
paling besar = biggest

Why is there no tense marker like “did” or “will”? How do we know if this is present, past, or future?

Indonesian verbs do not conjugate for tense. There is no change like talk / talked / will talk. Instead, time is understood from:

Time words:
- sekarang = now
- kemarin = yesterday
- besok = tomorrow
- tadi = earlier (today), etc.
Context.

In your sentence, “sekarang” (“now”) tells us the time frame:

Ilmuwan lain berbicara tentang iklim dan menjelaskan mengapa musim panas sekarang terasa lebih panas.
→ The natural reading is present / nowadays, something like:
“Other scientists talk about the climate and explain why summers now feel hotter.”

Is this sentence formal, neutral, or informal? How would it sound in more casual spoken Indonesian?

The sentence is neutral to slightly formal, suitable for news articles, textbooks, or explaining science.

A more casual / conversational version might be:

Ilmuwan lain ngomong soal iklim dan jelasin kenapa musim panas sekarang kerasa lebih panas.

Changes:

ngomong instead of berbicara (very informal “talk”)
soal instead of tentang (colloquial “about”)
jelasin instead of menjelaskan (spoken, shortened)
kerasa instead of terasa (colloquial pronunciation)

For learners, the original sentence is a good standard version to model.