Min veninde lægger sin notatbog og en blå kuglepen på bordet før forelæsningen.

Yes. Veninde means female friend, while ven means male friend or sometimes just friend in a more general sense.

So min veninde is specifically my female friend. It does not normally mean my girlfriend in the romantic sense; for that, Danish usually uses kæreste.

Because veninde is a singular common-gender noun, also called an en-word.

Danish possessives agree with the noun they go with:

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

So:

• min veninde
• mit bord
• mine venner

Because a possessive already acts as the determiner.

In Danish, you normally do not combine a possessive with en/et in this kind of phrase. So:

• sin notatbog = her own notebook
• not sin en notatbog

This works like English:

• her notebook
• not her a notebook

Because Danish uses a reflexive possessive when the owner is the same as the subject of the clause.

Here, the subject is min veninde, so sin means her own:

• Min veninde lægger sin notatbog ... = My friend puts her own notebook ...

If you said hendes notatbog, it would usually mean someone else’s notebook, not the friend’s own notebook.

Also, the form depends on the thing owned:

• sin for common-gender singular
• sit for neuter singular
• sine for plural

Examples:

• sin bog
• sit bord
• sine bøger

Because lægge means to lay / put / place something down.

It is used when someone causes an object to be placed somewhere:

• Hun lægger bogen på bordet = She puts the book on the table

A very important contrast is:

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

So:

• Hun lægger bogen på bordet = she puts it there
• Bogen ligger på bordet = the book is lying there

Yes. Danish present tense often covers both the simple present and the English progressive.

So lægger can mean:

• puts
• is putting

The exact English translation depends on context. In a standalone learning sentence like this, puts is often the most neutral translation, but is putting could also be natural in the right situation.

Because kuglepen is a singular common-gender noun, so it takes en.

The adjective also has the form that matches this pattern:

• en blå kuglepen

Compare:

• en blå bog
• et blåt bord

So the -t form appears with many neuter singular nouns, but not here, because kuglepen is an en-word, not an et-word.

Danish usually adds the definite article as an ending on the noun.

So:

• et bord = a table
• bordet = the table

and:

• en forelæsning = a lecture
• forelæsningen = the lecture

This is one of the big differences from English. Instead of a separate word like the, Danish often uses a suffix:

• -en for many common-gender nouns
• -et for many neuter nouns

You do get a separate definite word such as den/det when there is an adjective:

• bordet = the table
• det store bord = the big table

Because that is a very natural Danish order: verb + object + place + time.

So here you get:

• lægger = verb
• sin notatbog og en blå kuglepen = object
• på bordet = place
• før forelæsningen = time

This is similar to a common English order too:

• She puts her notebook and a blue pen on the table before the lecture

Other word orders are possible in Danish depending on emphasis, but this version is very normal and neutral.

Because Danish usually writes compound nouns as a single word.

So:

• notatbog = note + book = notebook
• kuglepen = ball + pen = ballpoint pen

This is very common in Danish. English often uses two words where Danish prefers one compound word.

For example:

• soveværelse = bedroom
• togstation = train station
• sommerferie = summer holiday

So these spellings are completely normal in Danish.