Nastavte monitor tak, aby byla obrazovka dobře vidět.

Nastavte is the imperative form of nastavit, which means to set, to adjust, or to position.

The ending -te is used for:

• you plural: speaking to more than one person
• you formal/polite singular: speaking politely to one person

So Nastavte monitor... means Adjust the monitor... or Set the monitor...

Nastav is the singular informal imperative, used when speaking to one person you address with ty.

• Nastav monitor... = informal singular
• Nastavte monitor... = formal singular or plural

So the sentence is either polite or addressed to multiple people.

This is about aspect.

• nastavit is perfective
• nastavovat is imperfective

In instructions, Czech often uses the perfective imperative when the action is seen as a single completed adjustment:

• Nastavte monitor... = Adjust/set the monitor as one task

If you used nastavujte, it could sound more like keep adjusting, adjust repeatedly, or focus on the process rather than the completed result.

Here monitor is the direct object of nastavte, so it is in the accusative case.

But monitor is a masculine inanimate noun, and for many such nouns, the accusative singular looks the same as the nominative singular.

So:

• nominative: monitor
• accusative: monitor

That is why the form does not visibly change.

Czech does not have articles like a or the.

So where English says:

• the monitor
• the screen

Czech simply says:

• monitor
• obrazovka

Whether something is understood as a or the depends on context.

tak, aby is a very common structure meaning so that or in such a way that.

In this sentence:

• Nastavte monitor tak, aby...
• Adjust the monitor so that...

It introduces the desired result of the adjustment.

You can think of it as:

• tak = so / in such a way
• aby = so that / in order that

Together they often function as one unit.

This is one of the most common things learners ask.

After aby, Czech often uses a form that looks like the past tense of být:

• aby byl
• aby byla
• aby bylo
• aby byli/byly

But here it does not mean past time.

So:

• aby byla obrazovka dobře vidět means so that the screen is clearly visible / can be seen well
• not so that the screen was visible

This is just how Czech forms many purpose or desired-result clauses after aby.

Because byla agrees with obrazovka.

Obrazovka is:

• feminine
• singular

So the form of být must also be feminine singular:

• obrazovka byla

If the noun were different, the form would change:

• monitor byl vidět
• okno bylo vidět
• obrazovky byly vidět

Because obrazovka is not the object of vidět here. It is the grammatical subject of the clause aby byla obrazovka dobře vidět.

The structure is roughly:

• the screen = subject
• was/is visible = predicate

So obrazovka stays in the nominative.

Even though English often says so that you can see the screen well, Czech expresses it more like so that the screen is well visible / can be seen well.

Být vidět is a very common Czech expression meaning:

• to be visible
• to be seen
• to be in view

Examples:

• Je vidět město. = The city can be seen.
• Odsud je dobře vidět. = It is easy to see from here.
• Obrazovka je špatně vidět. = The screen is hard to see.

In this expression, vidět stays in the same form. The word that changes is být:

• je vidět
• byla vidět
• bude vidět

So in your sentence, byla vidět means was/is visible in the aby construction.

Dobře is an adverb, and it modifies the expression být vidět.

So:

• dobře vidět = easy to see, clearly visible

You would not use dobrá here, because that is an adjective, and this sentence needs an adverb.

You could say:

• aby byla obrazovka dobře viditelná

That is grammatical and means something similar, but aby byla obrazovka dobře vidět is very natural and idiomatic in everyday Czech.

Yes, that variant is also possible.

Both are grammatical:

• aby byla obrazovka dobře vidět
• aby obrazovka byla dobře vidět

The version with byla right after aby is very natural and common. Czech word order is more flexible than English, and small changes can affect emphasis or rhythm rather than basic meaning.

In this sentence, the given order sounds neutral and natural.

You could translate it literally that way, but it would sound unnatural in English.

A better English rendering is:

• Adjust the monitor so that the screen is clearly visible.
• Adjust the monitor so that you can see the screen clearly.

This is a good example of how Czech and English package the same idea differently:

• Czech: the screen is visible
• English: often you can see the screen