Nilipoinua ndoo hii ya maji, mgongo wangu uliumia kidogo.

It is made of several parts:

• ni- = I
• -li- = past tense
• -po- = when / at the time that
• inua = lift, raise

So nilipoinua means when I lifted or when I raised.

A useful thing to notice is that Swahili often packs information that English would spread across several words into one verb form.

Kuinua is the dictionary form, meaning to lift.

When you actually conjugate the verb in a sentence, the ku- infinitive marker disappears, and you use the verb stem:

• dictionary form: kuinua
• stem used in conjugation: inua

So:

• kuinua = to lift
• nilipoinua = when I lifted

This is very normal in Swahili verbs.

In Swahili, demonstratives like this and that usually come after the noun.

So:

• ndoo hii = this bucket
• kitabu hiki = this book
• mtu huyu = this person

That is the usual Swahili word order, even though English puts this before the noun.

Literally, it is something like:

• ndoo = bucket
• hii = this
• ya maji = of water / for water

So ndoo hii ya maji means this bucket of water or this water bucket, depending on context.

In this sentence, the natural meaning is this bucket of water.

Ya is a connector often translated as of.

It links ndoo with maji:

• ndoo ya maji = bucket of water

The form of this connector changes to match the noun before it. Since ndoo belongs to the noun class that uses ya, you get ya maji.

So here ya does not mean possession in a strict English sense only; it can also show what something contains or is associated with.

In Swahili, possessives normally come after the noun.

So:

• mgongo wangu = my back
• kitabu changu = my book
• rafiki yangu = my friend

Also, the possessive changes form to agree with the noun class. That is why you get wangu here.

So the correct pattern is:

• noun + possessive

not

• possessive + noun

Because possessives in Swahili must agree with the noun class of the noun they describe.

Mgongo belongs to the noun class that takes the possessive form wangu for my.

Compare:

• mgongo wangu = my back
• mtoto wangu = my child
• kitabu changu = my book
• ndoo yangu = my bucket

So yangu is not the general form for every noun. The form changes depending on the noun class.

In uliumia:

• u- = subject marker for a singular noun in the same class as mgongo
• -li- = past tense
• umia = be hurt, feel pain, ache

So mgongo wangu uliumia means my back hurt or my back was a bit injured / in pain.

The important point is that the verb agrees with mgongo, because mgongo is the subject of that clause.

Usually kuumia means to be hurt, to feel pain, or to get injured.

So:

• mgongo wangu uliumia = my back hurt
• mguu umeumia = the leg is hurt
• nimeumia = I am hurt / I got hurt

English often says I hurt my back, but Swahili commonly expresses the body part itself as the subject:

• mgongo wangu uliumia = literally my back hurt

That is very natural in Swahili.

Kidogo means a little, slightly, or a bit.

Here it softens the statement:

• uliumia kidogo = hurt a little / was slightly hurt

So the sentence does not mean a serious injury necessarily—just some pain or a small strain.

That is a very common Swahili way to express pain or injury.

Instead of focusing on I, Swahili often focuses on the body part or the person affected:

• kichwa kinauma = the head hurts
• tumbo linauma = the stomach hurts
• mgongo wangu uliumia = my back hurt

So although English often says I hurt my back, Swahili naturally says something closer to my back got hurt or my back hurt.

Yes. That is a very good, natural translation.

Depending on context, English could also say:

• When I lifted this bucket of water, I hurt my back a little.
• When I picked up this bucket of water, my back started hurting a bit.

The Swahili structure is slightly closer to my back hurt a little, but English may use either version naturally.

Its main meaning here is when I lifted or when I was lifting in the sense of at the moment I lifted.

In many contexts, this form introduces the event during which something else happened. So English translations may vary a little:

• when I lifted
• as I lifted
• upon lifting

But in this sentence, when I lifted is the safest and most natural translation.

Yes, you could, because wakati means time or when.

So:

• Nilipoinua ndoo hii ya maji, ...
• Wakati nilipoinua ndoo hii ya maji, ...

Both can work.

However, nilipoinua already contains the idea of when, so adding wakati is often unnecessary unless you want extra emphasis or a slightly fuller style.