Můj dědeček nejraději sedí doma a čte noviny.

Because můj has to agree with dědeček (grandfather) in gender, number, and case.

• dědeček is masculine animate, singular, nominative
• so the possessive adjective is můj

Compare:

• můj dědeček = my grandfather
• moje babička = my grandmother
• moje auto = my car
• mého dědečka = my grandfather (in a different case, for example accusative or genitive in some contexts)

So here můj is correct because dědeček is the subject of the sentence.

Yes. Dědeček is a more affectionate or softer form of děda.

Very roughly:

• děda = grandpa
• dědeček = grandpa / grandad / dear grandpa

Both mean grandfather, but dědeček often sounds warmer, more affectionate, or more family-oriented. Learners will often see Czech using diminutive forms like this.

Nejraději comes from rád and is the superlative adverb form. It means something like:

• most gladly
• most willingly
• in natural English: likes best, prefers to

So:

• Rád čtu. = I like reading / I read gladly.
• Raději čtu. = I’d rather read.
• Nejraději čtu doma. = I like reading at home best / I most like to read at home.

In this sentence, nejraději expresses preference: this is what the grandfather likes doing most.

In Czech, nejraději often modifies the whole activity or situation, not just the single verb right next to it.

So Můj dědeček nejraději sedí doma a čte noviny means something like:

• What my grandfather likes best is sitting at home and reading newspapers.

It is not limited only to sedí. It naturally covers the whole coordinated activity:

• sedí doma
• a čte noviny

So the meaning is broader than just he most likes sitting.

Because the subject is můj dědeček, which is third person singular (he).

So the verbs are present tense, 3rd person singular:

• sedět → sedí = he sits / is sitting
• číst → čte = he reads / is reading

Czech does not need to say on (he) here, because the verb form already shows the person and number.

Czech often drops subject pronouns when they are not needed. This is very common.

English usually needs the pronoun:

• My grandfather likes sitting at home...
• He reads newspapers.

But Czech can simply say:

• Můj dědeček ... sedí ... a čte ...

The subject is already clear from můj dědeček, and the verb forms match it.

Doma means at home.

It describes location, not movement.

• Je doma. = He is at home.
• Sedí doma. = He sits at home.

By contrast, domů means homeward / to home and expresses movement:

• Jde domů. = He is going home.

So in your sentence, doma is correct because the grandfather is already there, sitting there.

Yes, noviny is grammatically plural. Czech treats newspaper as a plural noun here.

So:

• noviny = newspaper / newspapers

In many contexts, even when English uses singular newspaper, Czech uses noviny.

Examples:

• Čtu noviny. = I’m reading the newspaper.
• Kupuji noviny. = I’m buying a newspaper / newspapers.

This is just something learners have to get used to.

Because noviny is the direct object, and here its accusative plural form is the same as its nominative plural form.

So:

• nominative: noviny
• accusative: noviny

That is why you do not see a visible change here.

Usually it sounds like a habit, a general preference, or something he typically likes to do.

That comes mainly from:

• nejraději = likes best / prefers
• the present tense in Czech, which often expresses habitual action

So the sentence is best understood as something like:

• My grandfather most likes sitting at home and reading the newspaper.
• My grandfather likes to sit at home and read newspapers best.

It could describe a current scene in the right context, but on its own it sounds more general.

Yes. Czech word order is flexible, and changing it can shift emphasis.

The given sentence is natural:

• Můj dědeček nejraději sedí doma a čte noviny.

But Czech could also say things like:

• Můj dědeček sedí nejraději doma a čte noviny.
• Doma můj dědeček nejraději sedí a čte noviny.

These alternatives may sound slightly different in focus, but the core meaning stays similar. Czech word order is influenced a lot by emphasis and information structure, not only by strict syntax.

Yes, čte is a cluster that many English speakers find hard at first.

A rough guide:

• č sounds like ch in church
• t is a normal t
• e is like e in met (roughly)

So čte is approximately ch-te, said quite quickly together.

It may feel strange because Czech allows consonant clusters that English usually avoids. It gets easier with practice.

A simply means and.

It connects the two verbs:

• sedí doma
• čte noviny

So the grandfather is doing two coordinated actions:

• sitting at home
• reading newspapers

That part works very similarly to English.