Min søster lægger konfetti ved siden af tallerkenerne, men jeg synes, at pynten allerede er nok.

Because søster is a common-gender noun in Danish.

Danish possessive words change like this:

• min for singular common gender
• mit for singular neuter
• mine for plural

So:

• min søster = my sister
• mit hus = my house
• mine bøger = my books

When you use a possessive like min, din, hans, vores, and so on, Danish normally does not use a separate article.

So you say:

• min søster = my sister
  not min søsteren

This is similar to English, where you say my sister, not my the sister.

Konfetti is usually treated like a mass noun here, much like confetti in English.

So Danish often just says:

• lægger konfetti = puts confetti down

If you added an article, it would sound more specific in a different context, but in this sentence the general mass-noun use is the natural choice.

Lægger is the present tense of lægge, which often means to lay, to put down, or to place something.

Here it means that the sister is placing confetti beside the plates.

A very common thing learners ask about is the difference between lægge and ligge:

• lægge = to lay/put something somewhere
• ligge = to lie/be lying somewhere

So:

• Hun lægger konfetti... = She is putting confetti...
• Konfettien ligger... = The confetti is lying...

Ved siden af is a fixed expression meaning beside or next to.

It is best learned as one whole phrase:

• ved siden af tallerkenerne = beside the plates

Word-for-word, it is not very helpful to translate each part separately. Just remember it as a set phrase.

You will also hear it with different nouns after it:

• ved siden af stolen = next to the chair
• ved siden af mig = next to me

Because it is the definite plural form: the plates.

The noun forms are:

• en tallerken = a plate
• tallerkener = plates
• tallerkenerne = the plates

So in the sentence, tallerkenerne refers to specific plates, probably the ones on the table.

The comma before men is normal, because men means but and joins two main clauses.

The comma before at depends on comma style:

• jeg synes, at ...
• jeg synes at ...

Both can be seen in Danish, depending on whether the writer uses start comma. So the comma before at is often optional in modern usage, but many people still write it.

Because synes is used for a personal opinion or judgment.

Here, jeg synes means something like:

• I think
• I feel
• In my opinion

So:

• jeg synes, at pynten allerede er nok = I think the decoration is already enough

By contrast, tror is more about belief, guessing, or thinking something is true.

Compare:

• Jeg synes, det er flot = I think it is pretty
• Jeg tror, det regner senere = I think it will rain later

Not always.

You can say:

• Jeg synes, at pynten allerede er nok
• Jeg synes pynten allerede er nok

Both are possible.

Including at can make the sentence feel a bit clearer or more explicit, especially in writing. Leaving it out can sound slightly more direct or conversational.

Because after at, Danish uses subordinate clause word order.

In a main clause, the finite verb usually comes before sentence adverbs like allerede:

• Pynten er allerede nok

But in a subordinate clause introduced by at, the adverb comes before the finite verb:

• at pynten allerede er nok

This is a very important Danish pattern:

• main clause: hun kommer aldrig
• subordinate clause: at hun aldrig kommer

Because pynt often works like a collective or uncountable noun, meaning decoration in a general sense.

So pynten here means something like:

• the decoration
• the decorations as a whole
• the existing decor

Even though English might sometimes prefer the decorations, Danish often uses singular pynt in this kind of context.

Here nok means enough.

So:

• pynten allerede er nok = the decoration is already enough

Be careful: nok can also mean probably in other sentences.

For example:

• Det er nok rigtigt = That is probably true

But after er in this sentence, nok clearly means enough or sufficient.