Kursen börjar den femte februari.

Because kursen is the definite form of kurs.

• kurs = course
• kursen = the course

In Swedish, the definite article is often added as an ending instead of being a separate word. So where English says the course, Swedish says kursen.

Börjar is the present tense of the verb börja, which means to begin or to start.

• börja = infinitive, to begin
• börjar = present tense, begins / is beginning / starts

So:

• Kursen börjar = The course begins / starts

Swedish present tense verbs are often formed by adding -r to the infinitive, especially with verbs like börja.

Swedish often uses the present tense for scheduled future events, just like English sometimes does.

Compare:

• English: The course starts on February fifth
• Swedish: Kursen börjar den femte februari

This is very natural when talking about timetables, plans, or fixed events. You do not need a special future form here.

In Swedish dates, den is commonly used before an ordinal number.

• den femte februari = the fifth of February / February fifth

So den is part of the normal way of saying a date.

A useful pattern is:

• den + ordinal number + month

Examples:

• den första mars = March first
• den tionde april = April tenth
• den tjugofjärde december = December twenty-fourth

Because dates in Swedish use ordinal numbers, not ordinary counting numbers.

• fem = five
• femte = fifth

So for dates, Swedish says the equivalent of the fifth, not just five.

Examples:

• den tredje maj = May third
• den sjunde juni = June seventh
• den femte februari = February fifth

Swedish does not need a separate word like of in this date expression.

English can say:

• the fifth of February

But Swedish simply says:

• den femte februari

So the structure is just:

• den + ordinal + month

There is no extra linking word between the day and the month.

In Swedish, months are normally not capitalized.

So you write:

• februari
• mars
• juni

not:

• Februari
• Mars
• Juni

This is different from English, where month names are capitalized.

The word order is:

• Kursen = subject
• börjar = verb
• den femte februari = time expression

So the basic pattern is:

• Subject + verb + time

This is a very normal Swedish sentence structure.

Yes. Swedish often allows the time expression to come first, but then the verb must come before the subject.

So you can say:

• Kursen börjar den femte februari.
• Den femte februari börjar kursen.

That happens because Swedish follows the V2 rule in main clauses: the finite verb usually comes in the second position.

Usually, in normal speech and in a full date expression like this, den is expected.

So:

• den femte februari = normal

Without den, it can sound incomplete or less natural in many contexts.

In writing, Swedish sometimes uses numerals instead, such as:

• 5 februari
• den 5 februari

But when the date is written out in words, den femte februari is the standard form.

It can be used without a direct object, as it is here.

In this sentence:

• Kursen börjar = The course begins

The subject itself is the thing that begins, so no object is needed.

But börja can also be used with other structures, for example:

• Vi börjar kursen i februari. = We start the course in February.
• Lektionen börjar klockan nio. = The lesson starts at nine.

So börja is flexible.

A common written form is:

• den 5 februari

You may also see:

• 5 februari

In speech, though, you would normally say:

• den femte februari

So there is often a difference between how dates are written and how they are spoken.

Even if it is written with words, it is spoken as a normal date phrase:

• den
  • femte
    • februari

The important thing for a learner is that Swedish dates are usually said with an ordinal number, not a plain cardinal number.

So if you see 5 februari, you would normally still say:

• den femte februari

not just:

• fem februari