Baik saya mahupun jiran saya perlu pergi ke balai polis pagi ini.

No. In this sentence, baik is not being used with its usual meaning of good.

In the pattern baik ... mahupun ..., it is part of a fixed linking structure. So:

• baik by itself can mean good / fine / well
• but baik X mahupun Y works like both X and Y or whether X or Y, depending on context

So in this sentence, baik is grammatical, not descriptive.

It is a correlative structure meaning both me and my neighbour.

So:

• baik saya mahupun jiran saya = both I and my neighbour

This structure links two parallel elements. It is often a little more formal than just using dan.

Some similar patterns:

• baik lelaki mahupun perempuan = both men and women
• baik siang mahupun malam = both day and night

You could say Saya dan jiran saya perlu pergi ke balai polis pagi ini, and that would also be correct.

But baik ... mahupun ... gives a slightly different feel:

• saya dan jiran saya = simple I and my neighbour
• baik saya mahupun jiran saya = both I and my neighbour, with a bit more emphasis on including both parties

It can sound:

• more formal
• more written
• a little more emphatic

So the sentence is not just joining two nouns; it is stressing that the statement applies to both of them.

Because the two saya do different jobs:

• the first saya = I
• jiran saya = my neighbour

Malay often shows possession by putting the possessor after the noun:

• jiran saya = neighbour my = my neighbour
• rumah saya = my house
• kawan saya = my friend

So the second saya is not repetition for style; it is necessary to show possession.

Perlu means need to or it is necessary to.

In this sentence:

• perlu pergi = need to go

Compared with some other Malay words:

• perlu = need to / necessary to
• mesti = must / have to
• harus = must / should, often more formal

So perlu expresses necessity, but it is usually a little less forceful than mesti.

Because Malay verbs do not change form for person or number the way English verbs sometimes do.

In English, compare:

• I go
• she goes

In Malay, the verb stays the same:

• saya pergi
• dia pergi
• mereka pergi

The same is true for perlu and pergi here. Even though the subject is both me and my neighbour, the verb phrase stays unchanged:

• perlu pergi

Malay does not require subject-verb agreement like English does.

Ke means to when talking about movement toward a place.

So:

• pergi ke balai polis = go to the police station

This is different from di, which marks location:

• di balai polis = at the police station
• ke balai polis = to the police station

Because the verb is pergi (to go), the destination marker ke is the correct choice.

Balai polis means police station.

It is a normal fixed expression in Malay:

• balai = a station, post, or official building in certain contexts
• polis = police

So together:

• balai polis = police station

A learner should treat it as a common set phrase rather than trying to translate balai too literally every time.

Yes, it can go elsewhere. Pagi ini means this morning, and Malay is fairly flexible about where time expressions go.

This sentence puts it at the end:

• Baik saya mahupun jiran saya perlu pergi ke balai polis pagi ini.

You could also say:

• Pagi ini, baik saya mahupun jiran saya perlu pergi ke balai polis.

Both are natural. Putting pagi ini at the beginning can slightly highlight the time.

Also note:

• pagi ini = this morning

That is the normal order, not ini pagi for this meaning.

Yes, in standard Malay it is normally written as mahupun, as one word.

In this sentence, baik ... mahupun ... is a fixed pairing, so you should learn it as a unit.

If you have seen maupun, that is common in Indonesian. For standard Malay, mahupun is the form that matches this sentence.

It sounds mostly neutral to slightly formal.

The main reason is the structure baik ... mahupun ..., which is more formal than everyday dan in many situations.

Compare:

• Baik saya mahupun jiran saya perlu pergi ke balai polis pagi ini.
  • slightly more formal, more polished
• Saya dan jiran saya perlu pergi ke balai polis pagi ini.
  • simpler, more conversational

So a learner should understand the sentence easily, but in casual speech many speakers might choose the second version.