Spotřebič je nový a dokonce úsporný.

Because they agree with spotřebič, which is a masculine singular inanimate noun.

In this sentence, nový and úsporný are predicate adjectives after je (is), but they still agree with the noun in gender and number:

• spotřebič = masculine singular
• nový = masculine singular form of new
• úsporný = masculine singular form of economical / energy-saving

For comparison:

• pračka je nová = the washing machine is new
• auto je nové = the car is new
• spotřebiče jsou nové = the appliances are new

Spotřebič is a masculine inanimate noun.

That matters because Czech adjectives must agree with it:

• masculine animate: often different forms in some cases
• masculine inanimate: the pattern used here

In the nominative singular, masculine inanimate adjectives typically look like:

• nový
• úsporný
• levný
• moderní (some adjectives follow a different pattern)

So the sentence uses the correct adjective forms for a masculine inanimate subject.

Because Czech has no articles.

English says:

• The appliance is new
• An appliance is new

Czech usually just says:

• Spotřebič je nový.

Whether it means the appliance, an appliance, or just appliance depends on context.

So the lack of an article is completely normal.

Je is the 3rd person singular present tense of být (to be).

So:

• já jsem = I am
• ty jsi = you are
• on/ona/ono je = he/she/it is

In Spotřebič je nový, je means is.

Czech normally keeps this verb in the present tense, unlike some languages where to be can be omitted.

Dokonce means even, indeed, or in fact, depending on context.

Here it adds emphasis: the appliance is not only new, but even economical / energy-saving.

So the idea is something like:

• The appliance is new and even energy-efficient.

It suggests the second quality is somewhat surprising, impressive, or worth highlighting.

Because dokonce emphasizes the adjective that follows.

In:

• Spotřebič je nový a dokonce úsporný.

the focus is on úsporný: it is even economical.

Czech word order is fairly flexible, but this position is very natural because it makes the emphasis clear.
If you move dokonce, the emphasis can shift slightly.

Yes. That is a perfectly normal sentence.

The difference is:

• Spotřebič je nový a úsporný. = The appliance is new and economical.
• Spotřebič je nový a dokonce úsporný. = The appliance is new and even economical.

So dokonce adds extra emphasis and a sense of surprisingly / additionally.

Because a means and, and here it simply joins two coordinated adjectives:

• nový
• úsporný

In Czech, you normally do not put a comma before a in a simple structure like this.

So:

• Spotřebič je nový a úsporný. ✅

A comma would only appear in more specific sentence structures, not in this basic coordination.

A helpful approximation is:

spot-RZHEH-beech yeh NO-vee ah DO-kon-tseh OO-spor-nee

A few key pronunciation points:

• Czech stress is usually on the first syllable of each word:
  • SPOtřebič
  • NOvý
  • DOkonce
  • Úsporný
• č is like ch in church
• ř is a special Czech sound; learners often approximate it at first
• ý is a long vowel

You do not need perfect pronunciation immediately; the most useful things at first are:

1. stress the first syllable
2. keep long vowels clearly longer

It can overlap with all of those, depending on context.

For appliances, úsporný often means:

• energy-efficient
• economical to run
• energy-saving

So in this sentence, the most natural idea is probably that the appliance does not use much electricity, water, or other resources.

In other contexts, úsporný can also mean frugal or sparing.

Yes, if the subject is already clear from context.

Czech often drops the subject pronoun, and nouns can also be omitted when they are understood. So if you are already talking about the appliance, you can say:

• Je nový a dokonce úsporný.
  = It is new and even economical.

But if you are introducing the topic or want to be clear, keeping spotřebič is better.

The verb je would stay the same in the singular, but the adjectives would change to agree with the noun.

Examples:

• Pračka je nová a dokonce úsporná.
  feminine singular

• Auto je nové a dokonce úsporné.
  neuter singular

• Spotřebiče jsou nové a dokonce úsporné.
  plural

This is a very important Czech pattern: adjectives must match the noun in gender, number, and in many situations also case.

It is a normal and natural Czech sentence.

It is simple, clear, and idiomatic:

• Spotřebič je nový = straightforward statement
• a dokonce úsporný = natural way to add emphasis

A native speaker could absolutely say this, especially in everyday conversation, advertising, or product descriptions.