Ми перевірили подовжувач і всі електроприлади.

Перевірили is the past tense plural form of перевірити (to check / to inspect / to verify).

The ending -ли shows that the subject is plural. Since the subject is ми (we), the verb has to be plural:

• я перевірив / перевірила = I checked
• ми перевірили = we checked

So Ми перевірили... means We checked...

This is a question of aspect, which is very important in Ukrainian.

• перевірити = perfective → to check, with focus on the completed result
• перевіряти = imperfective → to be checking, to check repeatedly, or to describe the process

So:

• Ми перевірили подовжувач... = We checked the extension cord...
  This suggests the action was completed.

If you said:

• Ми перевіряли подовжувач...

that would sound more like We were checking the extension cord or We checked it (as a process / repeatedly), depending on context.

It is changing functionally, but for this noun the accusative form looks the same as the nominative.

Here, подовжувач is the direct object of перевірили, so it is in the accusative case.

For inanimate masculine nouns in Ukrainian, the accusative singular is usually the same as the nominative singular.

So:

• подовжувач = nominative
• подовжувач = accusative

That is why you do not see a visible change.

Because this phrase is also a direct object, so it is in the accusative plural.

However, for inanimate plural nouns, the accusative plural usually looks the same as the nominative plural.

So:

• електроприлади = nominative plural
• електроприлади = accusative plural

And всі agrees with the noun in number and case:

• всі електроприлади = all the electrical appliances

Подовжувач usually means an extension cord or extension lead.

Depending on context, it can sometimes also refer to something like a power strip, but the most basic meaning is an electrical extension device used to extend the reach of a cable.

So in this sentence, подовжувач is best understood as the extension cord.

Not exactly.

Електроприлади means electrical appliances / electrical devices. It refers to things that run on electricity, especially household or practical devices.

Examples might include:

• a heater
• a lamp
• a kettle
• a fan

It is not quite the same as electronics, which in English often suggests devices like phones, computers, tablets, etc.

So всі електроприлади is better translated as all the electrical appliances/devices rather than all the electronics.

Yes. Всі and усі both mean all and are often interchangeable.

So both of these are natural:

• всі електроприлади
• усі електроприлади

Sometimes speakers choose one over the other for rhythm, style, or regional preference, but both are standard.

Yes. In many contexts, і and та can both mean and.

So this sentence could also be:

• Ми перевірили подовжувач та всі електроприлади.

Both are correct.

Very generally:

• і is the most common basic word for and
• та is also common and often sounds a bit smoother in some contexts

Learners should be comfortable with both.

Yes, very often.

Because перевірили already shows a plural past form, the subject can be omitted if it is clear from context:

• Перевірили подовжувач і всі електроприлади.

This can still mean We checked the extension cord and all the electrical appliances, especially if the context already makes the subject obvious.

However, ми is included when the speaker wants to be explicit, contrastive, or simply clear.

No, Ukrainian word order is fairly flexible.

The neutral order here is:

• Ми перевірили подовжувач і всі електроприлади.

But other orders are possible, depending on emphasis:

• Подовжувач і всі електроприлади ми перевірили.
• Ми всі електроприлади і подовжувач перевірили.

These alternatives may sound more marked or emphatic. The original sentence is the most natural neutral version for most situations.

Because Ukrainian has no articles like English a / an / the.

So:

• подовжувач can mean an extension cord or the extension cord
• електроприлади can mean electrical appliances or the electrical appliances

You understand whether it is definite or indefinite from the context, not from an article.

Yes, it is one word.

It is a compound built from:

• електро- = electric / electrical
• прилад = device, appliance, instrument

So:

• електроприлад = electrical appliance/device
• електроприлади = electrical appliances/devices

This kind of compound is very common in Ukrainian.

Yes, depending on context.

Перевірити can mean:

• to check
• to inspect
• to verify
• sometimes to test

So if the speaker means they made sure the extension cord and appliances were working properly, tested may fit in English. If the idea is simply that they examined them, checked is the best basic translation.

In most learner contexts, checked is the safest default.