Learn Hardcore Swahili: Nimekuarifu kuhusu mkutano; tafadhali uwaarifu wazazi pia. - I have informed you about the meeting; please inform the parents too.

It segments as: ni- (I) + -me- (perfect aspect, “have”) + -ku- (you, singular, as object) + -arifu (inform). So it literally says “I-have-you-informed.”

Why use -me- (perfect) in Nimekuarifu instead of the simple past -li-?

-me- presents a completed action with present relevance: “I have informed you (so you now know).”
-li- is a plain past: Nilikuarifu = “I informed you,” typically tied to a specific past time (e.g., yesterday).
You’d prefer -me- when the result matters now; use -li- when narrating past events or adding a time adverb like “jana.”

What does kuhusu mean and how is it used?

Kuhusu means “about/regarding.” It takes a noun phrase:

kuhusu mkutano = about the meeting Alternatives:
juu ya mkutano (also “about,” a bit more colloquial)
… kwamba … to introduce a clause: Nimekuarifu kwamba mkutano utakuwa kesho (“I’ve informed you that the meeting will be tomorrow”).

Why is there a semicolon between the two clauses?

It links two closely related independent clauses. You could also use:

A period: Nimekuarifu … . Tafadhali uwaarifu …
A linker: …; halafu/kisha hivyo/na tafadhali uwaarifu … Semicolons are acceptable in Swahili prose much like in English.

What is happening morphologically in uwaarifu?

u- (you, singular, as subject) + -wa- (them, object marker for human plural/class 2) + -arifu (inform). Writing shows the vowels together: u + wa + arifu → uwaarifu (the double “aa” is normal, as in nawaambia “I tell them”).

Is uwaarifu an imperative?

It’s the subjunctive, used here as a polite request because of tafadhali (“please”).

Polite/subjunctive: Tafadhali uwaarifu wazazi = “Please (you) inform the parents.”
Bare imperative (2sg): Waarifu wazazi! = “Inform the parents!” (more direct) Note: With verbs that don’t end in -a (like -arifu, -safiri), the final vowel typically doesn’t change to -e in the subjunctive, so uwaarifu is correct.

Do I need the object marker -wa- if I also say wazazi?

It’s optional in this post-verbal position. You can say:

Tafadhali uarifu wazazi pia (no object marker)
Tafadhali uwaarifu wazazi pia (with object marker) Including -wa- is very common with definite human objects and sounds natural. If you front the object (topicalization), the object marker becomes obligatory: Wazazi, tafadhali uwaarifu pia.

Could I use a different verb for “inform,” like “tell”?

Yes, depending on tone/register:

Neutral/common: -ambia (tell) → Tafadhali uwaambie wazazi pia.
Neutral/formal: -julisha (inform) → Tafadhali uwajulishe wazazi pia.
Slightly formal: -fahamisha (make aware) → Tafadhali uwafahamishe wazazi pia.
More formal: -arifu (inform) as in the given sentence.

How do I make the polite negative: “Please don’t inform the parents”?

Use the negative subjunctive usi-:

Tafadhali usiwaarifu wazazi. (u- + si + wa + arifu)

How do I say it to more than one addressee (“you all”)?

Two natural options:

Polite subjunctive (2nd plural subject prefix m-): Tafadhali mwaarifu wazazi pia.
Plural imperative with -ni: Tafadhali waarifuni wazazi pia.

Can pia go in other positions?

Yes. It’s flexible, with slight differences in emphasis:

Tafadhali uwaarifu wazazi pia. (… inform the parents too.)
Tafadhali pia uwaarifu wazazi. (Please also inform the parents.)
Pia, tafadhali uwaarifu wazazi. (Also, please inform the parents.)

Does wazazi need a possessive (e.g., “my parents”)?

Not necessarily; wazazi can mean “the parents” from context. If you need to specify:

wazazi wangu = my parents
wazazi wao = their parents Example: Tafadhali uwaarifu wazazi wangu pia.

What noun class is mkutano, and what’s the plural?

It’s class 3/4 (m-/mi-):

singular: mkutano (meeting)
plural: mikutano (meetings) So: kuhusu mkutano / kuhusu mikutano.

Can I drop kuhusu and just say “inform you the meeting”?

With -arifu, you normally say “inform [someone] about [something]”: kumuarifu mtu kuhusu kitu. Alternatives:

Use kwamba with a clause: Nimekuarifu kwamba kutakuwa na mkutano.
Use a different verb pattern: Nimekwambia habari za mkutano. (“I told you the news about the meeting.”)

Could -wa- in uwaarifu mean “you all” instead of “them,” and is that ambiguous?

Yes, -wa- is both the 2nd plural object marker (“you all”) and the class 2/3rd plural human object marker (“them”). Context disambiguates. Here, the explicit noun wazazi makes it clear that -wa- = “them.” If you were addressing “you all” as the object, you’d typically avoid ambiguity by naming the noun or adjusting the sentence.