Наш полёт задерживается из-за сильного ветра.

Because полёт is a masculine singular noun, and наш has to agree with it in gender, number, and case.

• наш = masculine singular
• наша = feminine singular
• наше = neuter singular
• наши = plural

So:

• наш полёт = our flight

Полёт is in the nominative case because it is the subject of the sentence — the thing that is being delayed.

In this sentence:

• Наш полёт = the subject
• задерживается = is delayed / is being delayed

So the basic structure is:

• Наш полёт задерживается = Our flight is delayed

The -ся ending often makes a verb reflexive or gives it a more passive / intransitive meaning.

Compare:

• задерживать / задержать что-то = to delay something
  • Они задерживают рейс. = They are delaying the flight.
• задерживаться / задержаться = to be delayed

So:

• Наш полёт задерживается literally feels like Our flight is getting delayed / is being delayed

This is a very natural way in Russian to express what English often says with a passive construction: is delayed.

In Russian, the present tense is often used for something that is currently the case.

So задерживается means the flight is currently delayed or is being delayed right now.

This matches English quite well:

• Наш полёт задерживается. = Our flight is delayed.

It does not have to mean the delay is just starting at this exact second. It simply describes the current situation.

Из-за means because of or due to.

So:

• из-за сильного ветра = because of the strong wind

A useful thing to know: из-за is very commonly used for a cause, often one with a negative result or inconvenience.

Examples:

• из-за дождя = because of the rain
• из-за пробок = because of traffic jams
• из-за ошибки = because of an error

Because из-за requires the genitive case.

The dictionary forms are:

• сильный = strong
• ветер = wind

But after из-за, they change to the genitive:

• сильного
• ветра

So:

• из-за сильного ветра = because of the strong wind

This is adjective-noun agreement in the genitive singular:

• masculine adjective: сильный → сильного
• masculine noun: ветер → ветра

It is a normal case form, but it may look a little surprising at first.

The nominative is:

• ветер = wind

The genitive singular is:

• ветра

Many Russian nouns change their endings quite a bit between cases, so this is something you get used to over time.

A few forms of ветер:

• nominative: ветер
• genitive: ветра
• dative: ветру
• instrumental: ветром
• prepositional: ветре

So in this sentence, ветра is simply the genitive required by из-за.

Полёт is pronounced roughly like pa-LYOT.

Important points:

• The stress is on ё
• ё always indicates a stressed yo sound

So:

• полёт = flight

In many printed texts, Russian often writes е instead of ё, so you may sometimes see полет, but here the correct pronunciation is still полёт.

That matters because:

• полет could be misread if you do not know the word
• ё helps show the correct pronunciation clearly

Yes. Russian word order is more flexible than English word order.

The neutral order here is:

• Наш полёт задерживается из-за сильного ветра.

But you could also say:

• Из-за сильного ветра наш полёт задерживается.

This puts more focus on the reason: because of the strong wind.

The meaning stays basically the same, but the emphasis changes a little.

Yes, very often you can.

• полёт = flight, the act/journey of flying
• рейс = flight, trip, route, service

In travel contexts, especially airports and airlines, рейс is often very common:

• Наш рейс задерживается. = Our flight is delayed.

Both are understandable here, but рейс can sound a bit more like a specific scheduled airline flight, while полёт is a little more general.

Yes. Задерживается comes from the imperfective verb задерживаться.

Why imperfective?

Because the sentence describes an ongoing situation/state, not a single completed event.

• задерживаться = to be delayed / to be getting delayed
• задержаться = to get delayed, to end up delayed

In this sentence, the imperfective is the natural choice:

• Наш полёт задерживается = Our flight is delayed

If you used a perfective form, it would usually describe the fact that the flight got delayed as an event, not just its current status.