Belakangan ini saya sering lembur di kantor.

Yes. Belakangan ini means lately, recently, or these days, depending on context.

• belakangan = later / lately / recently
• ini = this

Together, belakangan ini is a fixed expression meaning lately / recently. In everyday English, Lately, I often work overtime at the office or Recently, I’ve been working overtime a lot would both match well.

In Indonesian, ini often comes after the noun or expression it modifies.

So:

• kantor ini = this office
• belakangan ini = lately / these days

This is normal Indonesian word order. English usually puts this before a noun, but Indonesian often puts ini after it.

Yes, lembur functions like a verb here, meaning to work overtime.

Indonesian often allows a root word to act as a verb in everyday speech, especially when the meaning is already clear from context. So:

• Saya lembur = I work overtime / I’m doing overtime
• Saya sering lembur = I often work overtime

You may also see bekerja lembur, which is a little more explicit:

• Saya sering bekerja lembur di kantor = I often work overtime at the office

But lembur by itself is very common and natural.

Because sering is an adverb of frequency, meaning often, and it usually comes before the verb or action.

So:

• saya sering lembur = I often work overtime

This is similar to English often, which also usually comes before the main verb:

• I often work
• Saya sering lembur

Di kantor means at the office or in the office.

• di = at / in / on, depending on context
• kantor = office

In this sentence, di kantor tells you the location where the overtime happens.

It does not mean to the office. For movement toward a place, Indonesian usually uses ke:

• ke kantor = to the office
• di kantor = at/in the office

Indonesian does not mark tense the way English does. There is no verb change like work / worked / have worked.

Instead, time is usually shown by time expressions and context. In this sentence, belakangan ini tells us the time frame: lately / recently. That makes the sentence understood as something happening in the recent present period.

So even though lembur itself does not change form, belakangan ini makes the meaning clear.

Sometimes yes, if the subject is already obvious from context. Indonesian often drops subjects when they are understood.

For example, in conversation:

• Belakangan ini sering lembur di kantor.

This can sound natural if everyone knows who is being talked about.

But including saya is clearer and more complete:

• Belakangan ini saya sering lembur di kantor.

For learners, keeping saya is usually a good idea.

Saya is neutral and polite. It works well in most situations, including with coworkers, people you do not know well, or in standard Indonesian.

Aku is more informal and personal. You can use it with friends, family, or in casual conversation:

• Belakangan ini aku sering lembur di kantor.

Both are grammatically fine. The choice depends on the relationship and level of formality.

Yes. Akhir-akhir ini is another very common way to say lately / recently / these days.

So these are both natural:

• Belakangan ini saya sering lembur di kantor.
• Akhir-akhir ini saya sering lembur di kantor.

They are very close in meaning. In many contexts, they are interchangeable.

Yes, it could move. Indonesian often puts time expressions at the beginning of the sentence to set the time frame first.

So this is natural:

• Belakangan ini saya sering lembur di kantor.

You could also say:

• Saya belakangan ini sering lembur di kantor.
• Saya sering lembur di kantor belakangan ini.

All of these are understandable, but the first version is especially natural because it immediately tells the listener when this is happening: lately.

No. They are different.

• sering = often
• selalu = always

So:

• Saya sering lembur = I often work overtime
• Saya selalu lembur = I always work overtime

Sering suggests something happens many times, but not every time. Selalu is much stronger.