Learn Hardcore Swahili: Je, umewahi kwenda baharini usiku? - Have you ever gone to the ocean at night?

At the beginning of a sentence, Je roughly corresponds to "Do/Does/Is/Are/Have…" in English when forming a question.
It doesn’t have a direct meaning by itself; it just marks the sentence as a question.

You do not have to use Je every time you ask a question. This sentence is also acceptable:

Umewahi kwenda baharini usiku?
Have you ever gone to the sea at night?

Swahili uses intonation and context to show something is a question, so Je is optional, but very common, especially in writing and in careful or formal speech.

What exactly does umewahi mean, and how is it different from just saying umekwenda or umeenda?

Umewahi comes from the verb kuwahi. In this context, umewahi means "have you ever (in your life)...".

u- = subject prefix for "you" (singular)
-me- = perfect tense/aspect marker (completed action with present relevance)
wahi = verb root wahi

So umewahi literally is "you-have-ever/had-the-chance", but idiomatically: "Have you ever…"

Comparisons:

Je, umewahi kwenda baharini usiku?
= Have you ever gone to the sea at night (at any time in your life)?
Je, umekwenda baharini usiku? or Je, umeenda baharini usiku?
= Have you gone to the sea at night (recently / on some specific occasion)?

Without wahi, it’s more neutral: just have you gone, not have you ever (at any time in your life).

How is umewahi formed grammatically? What are its parts?

Umewahi breaks down like this:

u- = subject prefix for 2nd person singular (you)
-me- = perfect tense/aspect marker
wahi = verb root from kuwahi

So the structure is:

u- + -me- + -wahi → umewahi

This is the standard Swahili verb template:
(Subject prefix) + (Tense/aspect marker) + (Object marker, if any) + (Verb root).

Why isn’t "you" written separately? Why don’t we see wewe in the sentence?

In Swahili, the subject is normally built into the verb using a subject prefix. In this sentence:

u- in umewahi already means "you (singular)".

So "you" is already present inside the verb form.

You can add wewe for emphasis:

Je, wewe umewahi kwenda baharini usiku?
= Have you (personally) ever gone to the sea at night?

But grammatically, wewe is not required; the verb alone shows the subject.

What is kwenda, and why does it start with k- instead of u- like umewahi?

Kwenda is the infinitive form of the verb "to go".

The infinitive in Swahili is formed with ku-
- verb root.
With the verb enda ("go"), the u changes to w after the syllable u in the tense marker, giving kwenda.

So:

dictionary form: kuenda (to go)
commonly realized as: kwenda after another vowel sound

In umewahi kwenda:

umewahi = "you have ever"
kwenda = "to go"

Together: "you have ever to go" → "you have ever gone". The infinitive kwenda comes after wahi to show what action you’ve ever done.

What does baharini mean exactly, and how is it different from bahari?

The noun bahari means "sea" / "ocean".

The form baharini is:

bahari (sea) + -ni (locative suffix)

The -ni suffix often means "in / at / on (that place)".

So:

bahari = the sea (as a thing)
baharini = "at the sea / at the seaside / in the sea"

In this sentence, baharini is best understood as "at the sea" or "by the sea", often understood like "at the seaside / at the beach".

Could I say kwa bahari or katika bahari instead of baharini?

Grammatically, kwa bahari or katika bahari could occur in some contexts, but they do not sound natural here.

baharini is the normal, idiomatic way to say "at the sea / at the ocean / at the seaside".
katika bahari would more literally suggest inside the sea, as in in the water, and is less natural for the idea of "going to the sea (as a place)" unless you really mean being in the sea.
kwa bahari is not the usual way to express location with bahari.

So for "go to the sea / go to the beach", you should say kwenda baharini.

Are there other words for "beach" besides baharini? What’s the difference?

Yes, there are other words:

pwani – coast, shore, seaside (also used more broadly for the coastal region)
ufukwe / ufukweni – beach, shore (often the sandy part)

Examples:

Ninaishi pwani. – I live on the coast.
Tunapenda kwenda ufukweni. – We like going to the beach.

In umewahi kwenda baharini, the focus is on the sea/ocean area in general. If you specifically mean the sandy beach, you might say:

Je, umewahi kwenda ufukweni usiku? – Have you ever gone to the beach at night?

What does usiku do in this sentence, and why isn’t there a word for "at" before it?

Usiku means "night".

In Swahili, time expressions like leo (today), jana (yesterday), kesho (tomorrow), asubuhi (in the morning), usiku (at night) are often used without a preposition.

So:

usiku here means "at night".
You don’t say "kwa usiku" or "katika usiku" for the normal time meaning.

The whole phrase:

baharini usiku = "at the sea at night".

Can I move usiku to another position in the sentence, like in English?

Yes, usiku (the time expression) is flexible in position, though the default is near the end.

All of these are understandable:

Je, umewahi kwenda baharini usiku?
Je, umewahi kwenda usiku baharini?
Je, usiku umewahi kwenda baharini?

(3) sounds a bit more marked, with extra emphasis on "at night". The first one is the most natural for a learner: …baharini usiku.

What tense/aspect is umewahi, and how would the sentence change with a different tense marker?

Umewahi uses the perfect aspect marker -me-, which usually means "have done" (with relevance to now).

u- = you (singular)
-me- = perfect ("have")
wahi = ever / have the chance

So:

Je, umewahi kwenda baharini usiku?
= Have you ever gone to the sea at night?

If you change the tense marker, the meaning changes:

Je, uliwahi kwenda baharini usiku?
li = past → Did you ever go to the sea at night? (more about a past period, less about your whole life)
Je, utawahi kwenda baharini usiku?
ta = future → Will you ever go to the sea at night?

Note how the middle part of the verb changes: u-me-wahi, u-li-wahi, u-ta-wahi, etc.