"Mwite daktari"

Translation: Call the doctor

[TessEwing1]

How does one know that the "mw-" is the direct object and not an indirect object? I.e., could it be "call him a doctor"?

[JasonFries2]

You would use the prepositional form of the verb to indicate indirect object

[ZanninaMargariti]

You should call the doctor is it right too???

[AGreatUserName]

In that case, it should also have the subject prefix, so umwite or mmwite. Without it, it's just imperative.

Yeah, mw- could also be the subject prefix if there's no object prefix, but the object prefix should be used here.

[mulsab]

I also thought it means 'Call him doctor'. How would you translate that?

[filixlan]

Why not "you (pl) got to be called by the doctor"??

[Annika986737]

Because it's not passive.

[vitoreiji]

Is it necessarily the doctor or could this also be "call a doctor"?

[aboutpurpo]

A suggestion for a fix for this (and most of the other grammar lessons, too.)
Most of these short sentences are ambiguous. Without context it is simply a guessing game. Perhaps they could title each lesson. Like "using objective prefixes in commands" or "direct commands." That way, at least we would not waste frustrating time guessing what the author wants.
Beyond that, allowing as correct any of the synonomous helping words like "heri, inafaa, afadhali, etc. Keeps us from guessing which one the author wants.

[gloucester5]

Why isn't 'you call the doctor' correct?