"Mereka berbicara dengan mantap."

Translation: They speak steadily.

[boringtomi]

Sorry but what does that mean???

[lockers001]

Not how I would have expressed this, but my wife said it is a normal expression. Her translation ... They speak well/good. And yes, she said mantap means steady. Again, different language, different colloquialisms. I have long accepted that I will never grasp these are there are far too many to learn.

[octavzlatior]

I imagine it is the opposite of doubt. Something like confidently?

[Cattuscattus]

Yes. That's how I interpreted it, which is why I thought: "They speak with steadiness." Confidence, firmness etc..

[Noel989771]

That is exactly what I wrote.

[evebergin1]

why is dengan used in this sentence?

[RamenDutchman]

Because “mantap” is a noun; it means “steadiness”
This sentence literally translates to “They speak with steadiness”

In natural English we'd say something like “They speak with confidence”

[Cattuscattus]

Why not "They speak with steadiness" ?

[Hans726]

They speak steadily means they speak with confidence, not doubtful..
Standing firm or being shy without confidence ate the two opposites

[stickyrenice]

I think when it's interpreted in english, it should be 'they speak confidently'

[aiYJ6q]

Is dengan necessary here. If so, then isn't mantap a noun.