Zonder muis kan Anna moeilijk tekenen, dus leent zij de muis van haar collega.

After zonder, Dutch often leaves out the article when speaking generally about lacking something: zonder jas, zonder bril, zonder muis. It means Anna does not have a mouse available.

You could also say zonder een muis, but that sounds more emphatic or more like without any mouse / without a particular mouse.
And zonder de muis would mean without the mouse, referring to a specific one.

This is because Dutch main clauses normally follow the verb-second rule. The finite verb must be in the second position.

Here, Zonder muis takes the first position, so the finite verb kan comes next, and the subject Anna comes after that:

• Zonder muis = first position
• kan = finite verb, second position
• Anna = subject

If the subject came first, the sentence could be:

Anna kan zonder muis moeilijk tekenen.

Both are correct, but the original sentence puts extra focus on zonder muis.

Because kan is a modal verb. In Dutch, when you use a modal verb such as kunnen, moeten, willen, or mogen, the other verb usually goes to the end of the clause.

So:

• kan = finite modal verb
• tekenen = main verb, placed at the end

That is why you get:

kan Anna moeilijk tekenen

and not kan Anna tekenen moeilijk.

Here moeilijk works as an adverb: it describes tekenen.

Dutch often uses the same form for both adjective and adverb. English usually distinguishes between difficult and difficultly, but Dutch normally just uses moeilijk.

So moeilijk tekenen means:

• to draw with difficulty
• to find drawing difficult

Again, this is the verb-second rule.

In the second clause, dus takes the first position. Since Dutch main clauses still want the finite verb in second position, leent must come next, and the subject zij follows it:

• dus = first position
• leent = finite verb, second position
• zij = subject

So dus leent zij is the normal Dutch order here.
Dus zij leent is not standard main-clause word order in this sentence.

Zij can mean either she or they, depending on the context.

Here it means she, because it refers back to Anna, which is singular. The verb also confirms that:

• zij leent = she borrows
• zij lenen = they borrow

So the form leent shows that this is singular.

Both are possible.

• zij is the full, stressed form
• ze is the unstressed, more everyday form

In writing, especially slightly more careful or formal writing, zij is common. In casual speech, many people would say:

dus leent ze de muis van haar collega

That would sound very natural too.

In the first clause, muis is mentioned in a general sense: Anna cannot really draw if she has no mouse available.

In the second clause, the sentence refers to a specific mouse, namely the one she borrows. That is why Dutch uses the definite article:

de muis

So the contrast is roughly:

• zonder muis = without a mouse, in general
• de muis = the mouse, a specific one in the situation

Yes. In Dutch, lenen is commonly used like this:

• iets lenen van iemand = to borrow something from someone

So in this sentence:

• leent ... de muis = borrows the mouse
• van haar collega = from her colleague

So van is the normal preposition here.

No. Haar here refers to Anna, not to the colleague's gender.

So haar collega means her colleague, and that colleague could be male or female. The noun collega itself does not tell you the gender.

If you wanted to specify, you could say:

• haar mannelijke collega = her male colleague
• haar vrouwelijke collega = her female colleague

Yes. Dutch uses muis for both the animal and the computer device.

Usually the context makes it clear which one is meant. In this sentence, because of tekenen and lenen, it is naturally understood as a computer mouse.