Learn Hardcore Vietnamese: Mặc dù vé rẻ nhưng xe buýt chạy rất nhanh. - Although the ticket is cheap, the bus runs very fast.

mặc dù … nhưng is a correlative conjunction used to express a concession (contrast). The first element (mặc dù) introduces the subordinate clause (“although…”), and the second element (nhưng) links to the main clause (“but…”). In English you might say “although… but…,” but note that in Vietnamese you generally keep both parts.

Why are both mặc dù and nhưng needed? Could I drop one of them?

In a standard concessive sentence you normally need both.

If you drop nhưng, you’d have to add another contrast marker like vẫn:
“Mặc dù vé rẻ, xe buýt vẫn chạy rất nhanh.”
If you drop mặc dù, you lose the clear signal of the subordinate clause.
So the simplest paired structure is mặc dù … nhưng ….

Do I need a comma after mặc dù vé rẻ?

Yes, when the subordinate clause comes first, it’s customary to place a comma before the main clause.
Correct punctuation:
“Mặc dù vé rẻ, nhưng xe buýt chạy rất nhanh.”
In casual writing or very short sentences you might see the comma omitted, but the comma helps signal the break.

Why isn’t there a linking verb like là between vé and rẻ?

In Vietnamese, adjectives can directly follow nouns without a copula.

vé rẻ literally reads “ticket cheap,” equivalent to English “cheap ticket” or “the ticket is cheap.”
Inserting là is unnecessary and would sound less natural in this context.

Why is rất placed before nhanh and not after?

rất is an adverb of degree (“very”) and in Vietnamese, degree adverbs precede the adjective or verb they modify.

Correct: rất nhanh (“very fast”)
Incorrect: nhanh rất

Why do we use the verb chạy for the bus instead of đi?

Vietnamese commonly uses chạy (“to run”) for vehicles, implying the mode of movement or operation of the vehicle.

Xe buýt chạy nhanh = “The bus runs/goes fast.”
While đi can mean “to go,” chạy is more specific to vehicles in motion.

Can I replace mặc dù with dù to make it more colloquial?

Yes. dù is a shorter, more informal alternative.
Example:
“Dù vé rẻ nhưng xe buýt chạy rất nhanh.”
Both sentences carry the same meaning; mặc dù is slightly more formal.

Could I reorder the clauses and say Xe buýt chạy rất nhanh, mặc dù vé rẻ?

Yes, you can put the main clause first and the concession clause second. It’s still correct and you should use a comma:
“Xe buýt chạy rất nhanh, mặc dù vé rẻ.”
However, starting with mặc dù tends to be more common when drawing attention to the contrast.