Ми чекаємо на зелене світло на перехресті.

Yes. Ukrainian often drops subject pronouns when the verb ending already makes the subject clear.

• чекаємо already means we wait / we are waiting
• so Чекаємо на зелене світло на перехресті is also natural

Keeping ми adds a little emphasis, contrast, or clarity, like we in English.

Чекаємо is the 1st person plural present form of чекати.

• чекати = to wait
• чекаємо = we wait / we are waiting

Ukrainian does not have a separate present continuous form like English are waiting, so the same form can cover both we wait and we are waiting. In this sentence, the natural English translation is usually we are waiting.

With чекати, Ukrainian can use more than one pattern. One very common everyday pattern is:

• чекати на + accusative

So:

• чекаємо на зелене світло = we are waiting for the green light

You may also hear forms without на, so this is not the only possible structure. But чекати на is very common and sounds completely natural here.

Yes. That is also a natural Ukrainian sentence.

Compare:

• чекаємо на зелене світло
• чекаємо зеленого світла

Both can mean we are waiting for the green light. The version with на is very common in speech and is very transparent for learners because the preposition clearly marks the thing being waited for.

Because світло is a neuter singular noun, and the adjective has to agree with it.

Adjective agreement in Ukrainian depends on:

• gender
• number
• case

So here:

• зелений = masculine
• зелена = feminine
• зелене = neuter

Since світло is neuter, the correct form is зелене.

It is in the accusative singular, but for many inanimate neuter nouns, the accusative looks exactly the same as the nominative.

So:

• nominative: зелене світло
• accusative: зелене світло

That is why nothing visibly changes here, even though the phrase is functioning as the object of чекаємо на.

In this context, it specifically means the green traffic light / the green signal.

Because the sentence also says на перехресті = at the intersection, the meaning is clearly traffic-related. So зелене світло is understood as the green light that lets you go.

Because the two instances of на do different jobs.

• на зелене світло = marks what we are waiting for
• на перехресті = tells us the location, at the intersection

It is completely normal in Ukrainian to use the same preposition more than once in one sentence if each one has a different function.

Because after на meaning location, Ukrainian uses the locative case.

The base form is:

• перехрестя = intersection

But after на when you mean at the intersection, it becomes:

• на перехресті

So:

• на перехрестя would suggest motion toward it
• на перехресті means being there

In natural English, it is at the intersection.

Even though the Ukrainian preposition is на, you should not translate prepositions word-for-word. Ukrainian на covers several meanings that English expresses in different ways. Here the natural English equivalent is at.

No. Ukrainian word order is fairly flexible.

The original sentence is a neutral, natural order:

• Ми чекаємо на зелене світло на перехресті.

But you could also say:

• На перехресті ми чекаємо на зелене світло.
• Ми на перехресті чекаємо на зелене світло.

These versions are still grammatical; they just shift the emphasis a bit. Putting на перехресті first highlights the location more.

Because Ukrainian has no articles.

English says:

• the green light
• the intersection

Ukrainian simply uses the noun phrase without an article:

• зелене світло
• перехресті

Whether something is definite or indefinite is usually understood from context. In this sentence, the situation makes it clear that we mean the specific traffic light at that intersection.