Vi såg paret nära vattenfallet.

This is the normal Swedish main-clause word order:

subject + verb + object + adverbial

So:

• Vi = subject
• såg = verb
• paret = object
• nära vattenfallet = adverbial / prepositional phrase

It matches very natural English word order: We saw the couple near the waterfall.

Swedish word order becomes more noticeable when something else comes first, but in a simple statement like this, this order is the standard one.

Yes. Såg is the past tense of se, which means to see.

So:

• se = to see
• ser = see / sees
• såg = saw
• sett = seen

This is an irregular verb, so you cannot predict såg from se just by adding a regular ending. You simply need to learn it as a verb form.

Examples:

• Jag ser honom. = I see him.
• Jag såg honom. = I saw him.
• Jag har sett honom. = I have seen him.

Paret means the couple or literally the pair.

The base noun is:

• ett par = a pair / a couple

To make it definite, Swedish usually adds the definite ending to the noun:

• ett par = a pair
• paret = the pair / the couple

So paret is not missing an article. The the idea is built into the ending -et.

This is very common in Swedish:

• ett hus = a house

• huset = the house

• ett bord = a table
• bordet = the table

Not always, but very often.

Ett par can mean:

• a pair
• a couple
• two / a few in some contexts

And paret can mean:

• the pair
• the couple

In a sentence like Vi såg paret, most people will naturally understand it as the couple, especially if the context involves two people together.

If the context were more neutral, it could also be understood more literally as the pair.

Here nära functions like a preposition meaning near or close to.

So:

• nära vattenfallet = near the waterfall

You do not need another preposition after it. Swedish says:

• nära huset = near the house
• nära skolan = near the school
• nära vattenfallet = near the waterfall

In other contexts, nära can also behave like an adjective or adverb, but in this sentence it is best understood as a preposition.

Because vattenfallet is the definite form: the waterfall.

The noun is:

• ett vattenfall = a waterfall
• vattenfallet = the waterfall

Again, Swedish usually puts definiteness at the end of the noun instead of using a separate word like the.

So:

• nära vattenfall would sound like near waterfall(s) or an indefinite/general idea, and would not fit the English meaning near the waterfall
• nära vattenfallet = near the waterfall

Because Swedish often expresses the by adding a suffix to the noun.

That is why you get:

• paret = the couple
• vattenfallet = the waterfall

This is one of the biggest differences from English. Instead of writing a separate word before the noun, Swedish often puts definiteness at the end.

Compare:

• en bok = a book

• boken = the book

• ett äpple = an apple
• äpplet = the apple

In this sentence, both nouns are definite, so both use the definite ending.

It can potentially be understood either way, just like in English.

Vi såg paret nära vattenfallet can mean:

• We saw the couple, and this happened near the waterfall.
• We saw the couple who were near the waterfall.

In many real situations, context makes the intended meaning clear. Swedish does not automatically remove this ambiguity.

If you want to be more explicit, you can rephrase:

• Vi såg paret som stod nära vattenfallet. = We saw the couple who were standing near the waterfall.
• Nära vattenfallet såg vi paret. = Near the waterfall, we saw the couple.

Swedish verbs do not change according to the subject the way they do in English.

So:

• jag ser = I see
• du ser = you see
• vi ser = we see
• de ser = they see

And in the past:

• jag såg
• du såg
• vi såg
• de såg

The verb form stays the same. That makes Swedish verb conjugation simpler than English in some ways.

Also, vi is only capitalized at the beginning of a sentence, just like ordinary pronouns in English. Swedish does not capitalize pronouns specially.

Yes, it is completely natural and idiomatic.

Vi såg paret nära vattenfallet is a normal, clear Swedish sentence. It sounds like something a native speaker could easily say in everyday narration.

A few close alternatives are also possible depending on emphasis:

• Vi såg paret vid vattenfallet. = We saw the couple by the waterfall.
• Vi såg paret i närheten av vattenfallet. = We saw the couple in the vicinity of the waterfall.

But the original sentence is perfectly good Swedish.