Orang tua saya menjaga keamanan kami setiap malam.

Literally, orang tua is old person (orang = person, tua = old).
But in everyday Indonesian, orang tua almost always means parents as a pair.

• orang tua saya → my parents
• orang tua kamu → your parents

If you want to say old person in a neutral/descriptive way, people more often say orang yang sudah tua or just rely on context. So in this sentence, everyone would understand orang tua saya as my parents, not my old person.

Indonesian usually shows possession by putting the possessed noun first, then the pronoun:

• orang tua saya = parents I → my parents
• rumah saya = house I → my house
• teman kami = friend we (exclusive) → our friend

So:

• orang tua = parents
• saya = I / me
• orang tua saya = my parents

There’s no separate word like my; word order plus the pronoun does the job.

Both saya and aku mean I / me, but they differ in formality:

• saya: neutral–polite, safe in almost all situations (speaking to strangers, in class, at work)
• aku: informal / intimate (speaking with close friends, family, or to children)

In many real-life contexts with family, people do say:

• orang tua aku = my parents (informal)

In a neutral sentence like the one you’re learning, orang tua saya is a bit more standard and polite, which is why textbooks typically use it.

Indonesian often leaves plurality to context, not form. There is no mandatory -s like in English. The phrase orang tua is fixed in usage and is normally understood as parents (plural) when used in the possessive pattern:

• orang tua saya → my parents (standard interpretation)
• orang tua mereka → their parents

If you really need to talk about one parent, you can specify:

• ayah saya = my father
• ibu saya = my mother
• salah satu orang tua saya = one of my parents

So you rely on how the phrase is typically used and the context.

Yes, both mean we / us, but:

• kami = we (exclusive) → we but not including the listener
• kita = we (inclusive) → we including the listener

In this sentence:

• Orang tua saya menjaga keamanan kami setiap malam.
  → My parents guard our safety every night.

The “we/us” here is the speaker and their group (e.g. their family), not including the person being spoken to. So kami is correct.

If the speaker really wanted to explicitly include the listener in that protected group, they could say kita, but that would change the meaning: our safety (mine + yours together).

Menjaga has a broad meaning that covers all of these, depending on context:

• to guard / watch over (like a security guard)
• to look after / take care of (children, health, etc.)
• to maintain / keep (a condition or state)

In this sentence:

• menjaga keamanan kami ≈ to guard our safety / to keep us safe

Some rough comparisons:

• menjaga anak = look after / take care of a child
• menjaga rumah = guard / watch the house
• menjaga kesehatan = maintain one’s health

So here it has both the idea of protecting and maintaining safety.

The root word is aman, which means safe (adjective).
Indonesian often makes abstract nouns using ke- … -an around an adjective or root:

• aman → ke-aman-an → keamanan = safety / security
• indah (beautiful) → keindahan (beauty)
• penting (important) → kepentingan (interest / importance)

So:

• keamanan = safety / security (noun)
• menjaga keamanan = to guard/maintain safety / to ensure security

Both are possible, with slightly different focus:

• menjaga kami = guard us directly
• menjaga keamanan kami = guard our safety / maintain the security around us

Menjaga kami sounds more like physically guarding people:

• Orang tua saya menjaga kami setiap malam.
  → My parents watch over us every night.

Menjaga keamanan kami emphasizes the condition of safety or security, not just the people. It can suggest things like locking doors, checking the environment, being alert, etc. That’s why keamanan (safety/security) is used.

Indonesian usually doesn’t change the verb form for tense. Instead, it uses time words and context.

In this sentence, setiap malam (every night) shows that it’s a habitual action in general time (similar to English present simple):

• setiap malam = every night
• tadi malam = last night
• malam ini = tonight
• besok malam = tomorrow night

So:

• Orang tua saya menjaga keamanan kami setiap malam.
  = My parents keep us safe every night (habitually / regularly).

Yes, setiap and tiap both mean every / each and are often interchangeable:

• setiap malam ≈ tiap malam = every night
• setiap hari ≈ tiap hari = every day

Setiap is a bit more formal/standard; tiap feels slightly more casual/colloquial, but both are very common in speech and writing. The meaning of the original sentence won’t change if you say:

• Orang tua saya menjaga keamanan kami tiap malam.

Yes, you can say:

• Orang tua saya menjaga kami setiap malam.

This is grammatically correct and means:

• My parents watch over us every night.

Differences:

• menjaga keamanan kami focuses on safety/security as a concept.
• menjaga kami focuses directly on us as people.

Both are natural; which one you choose depends on which nuance you want.