Мастер пришёл вовремя и быстро починил выключатель.

Here мастер usually means something like repairman, technician, handyman, or service worker, depending on context.

In this sentence, because he fixes a switch, мастер is most naturally understood as the repairman / technician.

So although мастер is related historically to master, in everyday Russian it often refers to:

• someone skilled at a trade
• a person who comes to repair or install something
• a craftsman

Context decides the best English translation.

Пришёл is the past tense, masculine singular form of the verb прийти (to come / to arrive).

It matches the subject мастер, which is:

• singular
• masculine

In the Russian past tense, verbs agree with the subject in gender and number:

• мастер пришёл = the repairman came
• мастерица пришла = the female craftsperson came
• мастера пришли = the repairmen came

So пришёл is used because the subject is one male person.

Russian often leaves out subject pronouns when the subject is already clear.

Here the noun мастер is explicitly stated, so there is no need to add он (he). Russian prefers not to repeat pronouns unnecessarily.

Compare:

• Мастер пришёл вовремя и быстро починил выключатель.
  = The repairman arrived on time and quickly fixed the switch.
• Он пришёл вовремя и быстро починил выключатель.
  = He arrived on time and quickly fixed the switch.

Both are possible, but with мастер already present, adding он would usually sound redundant.

This is mainly about aspect and meaning.

Пришёл comes from прийти, which is perfective. It means the person arrived, with the result that he is now there.

So:

• пришёл = came / arrived successfully
• шёл = was walking / was on the way
• приходил = used to come / came on some occasion, often without focus on the completed arrival as the key result

In this sentence, the idea is a sequence of completed actions:

1. he arrived on time
2. he fixed the switch

That is why пришёл fits best.

Again, this is about aspect.

• починил is perfective: he fixed it completely, with a finished result
• чинил is imperfective: he was fixing it / used to fix it / worked on fixing it

Since the sentence describes a completed action with a clear result, Russian uses починил.

Compare:

• Он быстро починил выключатель.
  = He quickly fixed the switch.
  (The switch ended up repaired.)
• Он быстро чинил выключатель.
  = He was fixing the switch quickly.
  (This describes the process, not necessarily the result.)

Вовремя is an adverb meaning on time, at the right time, or punctually.

So:

• пришёл вовремя = arrived on time

A very important point for learners:

• вовремя (one word) = on time
• во время (two words) = during

For example:

• Мастер пришёл вовремя. = The repairman arrived on time.
• Во время ремонта было шумно. = During the repair, it was noisy.

That spelling difference matters.

Быстро is an adverb meaning quickly, and Russian word order is fairly flexible.

Here быстро починил is a very natural neutral order:

• и быстро починил выключатель

You could also say:

• и починил выключатель быстро

But that may sound slightly different in emphasis. Putting быстро before the verb is common when you just want to state the action naturally.

Russian word order often changes to highlight different parts of the sentence, but this version is standard and neutral.

It is in the accusative case here, because it is the direct object of починил.

However, for many inanimate masculine singular nouns, the accusative looks exactly like the nominative.

So:

• nominative: выключатель
• accusative: выключатель

That is normal.

Compare with a feminine noun, where the accusative often looks different:

• лампа → лампу

So in:

• Мастер починил выключатель the noun is accusative in function, even though its form does not change.

There is no comma because и connects two verbs with the same subject:

• пришёл
• починил

Both actions belong to мастер, so Russian does not put a comma there in a simple sentence like this.

Structure:

• Мастер [пришёл вовремя] и [быстро починил выключатель].

A comma would normally appear if there were separate clauses with different subjects or a more complex structure.

Its basic meaning here is and.

However, because the verbs describe actions in sequence, English may naturally understand:

• The repairman arrived on time and quickly fixed the switch or even
• The repairman arrived on time and then quickly fixed the switch

Russian и itself still means and, but context often gives a sense of sequence:

1. he arrived
2. he fixed the switch

So then is an implied idea, not a separate word in the Russian sentence.

Yes. Пришёл is pronounced with ё, roughly like prishyol.

In printed or informal Russian, ё is often written as е, so you may see:

• пришел

But the correct pronunciation is still пришёл, not пришел with a plain e sound.

For learners, it is helpful to remember:

• written fully: пришёл
• often written in everyday text: пришел
• pronunciation: with yo

This is very common in Russian spelling.