kono kaban ni wa nootopasokon ga hairimasen.

topic particle

Breakdown of kono kaban ni wa nootopasokon ga hairimasen.

• が: subject particle
• この: this
• に: location particle

Questions & Answers about kono kaban ni wa nootopasokon ga hairimasen.

Why is it に は after このかばん, instead of just に?

に marks the destination or container with the verb 入る: something goes into the bag.

Adding は after に makes that whole phrase the topic: as for in this bag / in this bag, ...

So:

• このかばんにノートパソコンが入りません。 = a more neutral statement
• このかばんにはノートパソコンが入りません。 = puts focus on this bag, often with a slight contrast such as in this bag, a laptop won’t fit

That は often sounds like there may be other bags where it would fit.

Why is ノートパソコン marked with が and not を?

Because 入る is an intransitive verb.

With 入る, the thing that goes in or fits is treated as the subject, so it takes が:

• ノートパソコンが入る = the laptop fits / goes in

English often uses an object in this kind of idea, but Japanese does not here.

If you use the transitive verb 入れる meaning to put in, then you would use を:

• ノートパソコンをかばんに入れる = to put the laptop into the bag

So in your sentence, the laptop is not a direct object; it is the thing that does or does not fit.

What does 入りません mean exactly here?