Brojčanik i mehanizam rade slično.

A word-by-word breakdown is:

• brojčanik = dial, clock face, or watch face depending on context
• i = and
• mehanizam = mechanism
• rade = work / operate
• slično = similarly / in a similar way

So the sentence structure is basically:

• Brojčanik
  • i
    • mehanizam = the dial and the mechanism
• rade = work
• slično = similarly

Because the subject is plural.

The sentence has two things joined by i (and):

• brojčanik
• mehanizam

Together, they form a plural subject: the dial and the mechanism.

So Croatian uses the 3rd person plural form of raditi (to work):

• radi = he/she/it works
• rade = they work

Compare:

• Brojčanik radi slično. = The dial works similarly.
• Brojčanik i mehanizam rade slično. = The dial and the mechanism work similarly.

They are in the nominative singular.

That is because they are the subjects of the sentence:

• brojčanik = nominative singular
• mehanizam = nominative singular

Even though the whole subject is plural in meaning because of and, each noun itself stays in its singular nominative form.

This is just like English:

• the dial
  • the mechanism = plural subject together

Because slično is being used as an adverb, not an adjective.

Here it describes how they work:

• rade slično = they work similarly

So:

• sličan / slična / slično can be adjective forms meaning similar
• slično can also function adverbially, meaning similarly

Compare these two ideas:

• Brojčanik i mehanizam su slični. = The dial and the mechanism are similar.
  Here slični is an adjective describing the nouns.

• Brojčanik i mehanizam rade slično. = The dial and the mechanism work similarly.
  Here slično describes the verb rade.

They are related, but not the same.

• rade slično = they function in a similar way
• su slični = they are similar

So the first one focuses on behavior or operation, while the second focuses on general similarity.

Examples:

• Brojčanik i mehanizam rade slično.
  Their operation is similar.

• Brojčanik i mehanizam su slični.
  They resemble each other in some way.

Because Croatian usually does not need subject pronouns when the verb already shows the person and number.

The verb rade already tells you the subject is they.

So Croatian commonly says:

• Brojčanik i mehanizam rade slično.

and not:

• Oni rade slično.

unless oni is needed for emphasis or contrast.

This is very normal in Croatian. It is a pro-drop language.

The basic word order here is natural and neutral:

• Brojčanik i mehanizam rade slično.

But Croatian word order is fairly flexible, so other orders are possible depending on emphasis. For example:

• Slično rade brojčanik i mehanizam.
  This puts more focus on similarly.

• Brojčanik i mehanizam slično rade.
  Possible, though less neutral in many contexts.

The most standard version for a learner is the original one: Brojčanik i mehanizam rade slično.

Not necessarily.

Brojčanik can refer to a dial, face, or numbered display, depending on the object. In context, it could mean:

• a clock face
• a watch face
• a dial on an instrument or device

So the exact English translation depends on context.

A simple approximate pronunciation is:

BROY-cha-neek ee meh-ha-NEE-zam RAH-deh SLEECH-no

A few useful sound notes:

• j is pronounced like English y
• č sounds like ch in chocolate
• h is pronounced clearly, not silent
• c in slično is part of č, so slično sounds roughly like SLEECH-no

This is only an approximation, but it should help you get started.

The infinitive is raditi, meaning to work or to do/work on, depending on context.

A few present-tense forms are:

• radim = I work
• radiš = you work
• radi = he/she/it works
• radimo = we work
• radite = you all / you formal work
• rade = they work

So in this sentence:

• rade = they work

Then the verb would become singular.

For example:

• Brojčanik radi slično. = The dial works similarly.
• Mehanizam radi slično. = The mechanism works similarly.

So:

• one subject → radi
• two or more coordinated subjects → rade

That is why Brojčanik i mehanizam rade slično uses the plural verb.