Jeg har fire bøger i min taske.

Yes. Jeg means I, and Danish normally requires an explicit subject in ordinary statements, just like English does.

So:

• Jeg har ... = I have ...
• You would not usually drop jeg in a normal sentence.

Danish is not a language where the subject is regularly left out.

Because Danish verbs are much simpler than English verbs in this way. The verb at have = to have, and in the present tense it stays har for all persons:

• jeg har = I have
• du har = you have
• han/hun har = he/she has
• vi har = we have
• de har = they have

So unlike English, Danish does not add a special -s form like has.

Because when a noun is used with a number, Danish normally uses the indefinite plural with no article.

So:

• en bog = a book
• to bøger = two books
• fire bøger = four books

You do not say an extra word equivalent to a/an before plural nouns after numbers.

The base form is bog = book.

Its common forms are:

• bog = book
• bogen = the book
• bøger = books
• bøgerne = the books

So bøger is the indefinite plural form. This is a good noun to notice because the vowel changes from o to ø in the plural, so it is not formed by just adding a simple ending to bog.

Because taske is a common gender noun in Danish, an en-word:

• en taske = a bag

With common gender singular nouns, you use min:

• min taske = my bag

Compare:

• min bil = my car
• mit hus = my house
• mine bøger = my books

So the possessive must match the noun being possessed, not the person who owns it.

Because in Danish, a possessive like min usually replaces the indefinite article.

So you say:

• min taske = my bag

not something like:

• min en taske

This is the same basic idea as in English: we say my bag, not my a bag.

Yes, it could. The sentence as written follows a very normal pattern:

• Subject + verb + object + place
• Jeg
  • har
    • fire bøger
      • i min taske

You can also move the place phrase to the front:

• I min taske har jeg fire bøger.

That is still correct Danish. When something other than the subject comes first, Danish usually puts the verb before the subject. This is the famous verb-second pattern.

So:

• Jeg har fire bøger i min taske.
• I min taske har jeg fire bøger.

Both are correct, but the second gives more focus to in my bag.

Because i is the normal preposition for in/inside.

Here it shows location inside the bag:

• i min taske = in my bag

Some related prepositions are:

• på = on
• under = under
• ved = by/near
• hos = at someone’s place / with someone

So if the books are inside the bag, i is the natural choice.

Normally no, unless you literally mean the books are on top of the bag. For books carried inside a bag, Danish uses i.

So:

• i min taske = in my bag
• på min taske = on my bag

That change of preposition changes the physical meaning.

Because min taske already means my bag, and that is normally enough by itself.

In Danish, when you use a possessive like min, the noun usually appears without the attached definite ending:

• taske = bag
• tasken = the bag
• min taske = my bag

So you generally do not combine min with tasken in ordinary standard Danish.

Yes. Jeg har ... can often correspond to both I have ... and I’ve got ... in natural English.

In Danish, har is the normal everyday verb here. There is no separate structure needed to express the idea of possession in this sentence.

Right — it is not pronounced like English spelling might suggest.

In most standard Danish pronunciation, jeg sounds approximately like yai or yigh, depending on speaker and context. The final g is not pronounced like a hard English g.

Also, in fast everyday speech, jeg is often reduced a lot, sometimes sounding closer to ya.

So learners should be prepared for the fact that the spoken form may sound quite different from the written form.

In careful pronunciation, each word is present clearly:

• Jeg har fire bøger i min taske.

But in natural speech, Danish often reduces unstressed words. For example:

• jeg may sound shorter
• har may be lighter than an English learner expects
• i min may flow together smoothly

A useful learning point is that spoken Danish often sounds more compressed than the spelling suggests, so it helps to learn both the written grammar and the real spoken rhythm.

You would need a different sentence structure and usually a definite form:

• Bøgerne er i min taske. = The books are in my bag.

Here:

• bøgerne = the books
• er = are

So in your original sentence, fire bøger is just an indefinite quantity, while bøgerne refers to specific books already known in the conversation.

Yes, if the possessed noun is plural.

Compare:

• min taske = my bag
• mine bøger = my books

So if you changed the sentence to talk about my four books, you could say:

• Jeg har mine fire bøger i min taske.

But notice the meaning changes slightly: mine fire bøger sounds more like my four specific books, not just four books in general.

Yes, it is a completely normal, natural sentence.

It is simple and neutral in style:

• Jeg = subject
• har = present tense verb
• fire bøger = indefinite plural object after a number
• i min taske = location phrase

So it is a very good example of basic Danish sentence structure.