Pumasok ka muna sa bahay dahil malakas ang ulan.

Yes. Pumasok ka muna sa bahay is being used as a command: Go inside the house first / Come into the house for now.

A very common pattern in Filipino is to start the sentence with the verb. So instead of English You go inside the house first, Filipino naturally puts the verb first:

• Pumasok = go in / enter / come in
• ka = you
• muna = first / for now / in the meantime

So the structure is very natural for Filipino:

• Pumasok ka muna... = Go inside first...

Also, pumasok comes from the root pasok with -um-, making it an actor-focus verb.

Here, pumasok means to go in, to enter, or to come inside.

The exact English translation depends on context. Filipino does not always separate go in and come in as sharply as English does. So in this sentence, pumasok ka muna sa bahay could be understood as:

• Go inside the house first
• Come into the house first
• Enter the house for now

All of those are reasonable translations depending on who is speaking and where they are.

Because Filipino commonly places the verb first, and short pronouns like ka often come right after it.

So:

• Pumasok ka = You go in / Go in
• not usually Ka pumasok

Here, ka is the second-person singular pronoun, meaning you.

This is a normal Filipino pattern:

• Umupo ka. = Sit down.
• Kumain ka. = Eat.
• Pumasok ka. = Go inside.

Muna is a very common Filipino particle that means something like:

• first
• for now
• in the meantime

In this sentence, it softens the command and gives the sense:

• Go inside first
• Go inside for now

So muna often suggests that this is the best thing to do at the moment, possibly before doing something else later.

Compare:

• Pumasok ka sa bahay. = Go inside the house.
• Pumasok ka muna sa bahay. = Go inside the house first / for now.

The version with muna sounds more natural and gentler in many situations.

Sa bahay means to the house, in the house, or at the house, depending on context.

In this sentence, sa bahay marks the destination or place:

• pumasok sa bahay = go into the house / enter the house

The marker sa is commonly used for locations and directions.

So:

• bahay = house
• sa bahay = to/at/in the house

Even though English says into the house, Filipino often just uses sa bahay with a verb like pumasok.

Yes, it could.

• sa bahay = into the house / at the house / in the house
• sa loob ng bahay = inside the house

Pumasok ka muna sa bahay already clearly means go inside the house, so sa loob ng bahay is not necessary.

If you say:

• Pumasok ka muna sa loob ng bahay

it sounds a bit more explicit: Go inside the house first, with extra emphasis on being inside.

Both are correct, but sa bahay is simpler and very natural.

Dahil means because.

So:

• dahil malakas ang ulan = because the rain is strong / because it is raining hard

A very common alternative is kasi, which also means because:

• Pumasok ka muna sa bahay dahil malakas ang ulan.
• Pumasok ka muna sa bahay kasi malakas ang ulan.

Both are natural, but there is a slight difference in tone:

• dahil can sound a bit more neutral or slightly more formal
• kasi is very common in casual speech

In everyday conversation, many speakers would probably use kasi, but dahil is completely normal.

That is because Filipino often uses a predicate-first structure.

In malakas ang ulan:

• malakas = strong / heavy
• ang ulan = the rain

Literally, yes, it is like Strong is the rain. But natural English is:

• the rain is strong
• more idiomatically: the rain is heavy
• or it is raining hard

This is a very common Filipino sentence pattern:

• Mainit ang kape. = The coffee is hot.
• Mabait ang bata. = The child is kind.
• Malakas ang ulan. = The rain is strong/heavy.

So the adjective often comes first, followed by the ang phrase.

Both are possible, but they mean slightly different things in emphasis.

• Malakas ang ulan = The rain is heavy.
• Umuuulan nang malakas = It is raining hard.

The first one focuses on the rain as a thing that is strong/heavy. The second one focuses more on the action of raining.

In your sentence, dahil malakas ang ulan is very natural and common. It sounds like giving a reason:

• Go inside first because the rain is heavy.

Another natural version would be:

• Pumasok ka muna sa bahay dahil umuulan nang malakas.

So both work.

Here, ang marks the subject/topic of the clause.

In malakas ang ulan:

• malakas is the predicate
• ang ulan is the subject/topic

So ang ulan means the rain in a grammatical sense.

This is a very common Filipino structure:

• Maganda ang panahon. = The weather is nice.
• Malamig ang tubig. = The water is cold.
• Malakas ang ulan. = The rain is heavy.

Yes. Ka is singular you.

If you are speaking to more than one person, use kayo:

• Pumasok kayo muna sa bahay dahil malakas ang ulan.

That means:

• You all go inside the house first because the rain is heavy.

Also, kayo can be used respectfully for one person, depending on context.

Because short pronouns like ka usually come before particles like muna in this position.

So the natural order is:

• Pumasok ka muna not
• Pumasok muna ka

This ordering is very common in Filipino:

• Kumain ka muna. = Eat first.
• Umupo ka muna. = Sit down first.
• Maghintay ka muna. = Wait first.

So a useful pattern is:

Verb + pronoun + particle

It sounds like a normal, fairly gentle command or suggestion.

What makes it softer:

• muna makes it less abrupt
• the reason clause dahil malakas ang ulan explains why

So it does not sound like a harsh order. It sounds more like practical advice or caring instruction:

• Go inside first because the rain is heavy.

If you removed muna, it could sound a bit more direct:

• Pumasok ka sa bahay...

If you changed the tone of voice, it could sound more urgent or more caring.

Yes.

English often distinguishes:

• go inside = movement away from the speaker
• come inside = movement toward the speaker

Filipino pumasok does not always force that same distinction. Context decides whether English should use go in, come in, or enter.

So depending on the situation, this could be translated as:

• Go inside the house first because the rain is heavy.
• Come inside the house first because the rain is heavy.

Both can be correct.

The root word is pasok, which is related to entering or going in.

The form pumasok is an -um- verb form, where -um- is inserted after the first consonant:

• pasok → pumasok

This is a very common verb pattern in Filipino.

Other examples:

• alis → umalis = leave
• upo → umupo = sit down
• takbo → tumakbo = run

So pumasok is part of a common actor-focus verb pattern.

You can roughly break it down word by word, but the natural English translation should be smoother.

A close breakdown is:

• Pumasok = go in / enter
• ka = you
• muna = first / for now
• sa bahay = to/in the house
• dahil = because
• malakas = strong / heavy
• ang ulan = the rain

A very literal version might be:

• Go in you first to the house because strong the rain.

But natural English would be:

• Go inside the house first because the rain is heavy.
• Come inside first because it’s raining hard.

So it is better to understand the Filipino structure, not translate every word mechanically.