وقتی وارد اداره شدم، همکارم داشت با تلفن صحبت میکرد.

وقتی means when in this sentence.

It introduces a time clause:

• وقتی وارد اداره شدم = when I entered the office

So the whole sentence is built like:

• When I entered the office, ...
• then the main clause tells you what was happening at that time.

This is a very common Persian pattern.

• وارد = entered / entering / into
• شدن = to become

But together, وارد شدن means to enter.

So:

• وارد اداره شدم literally looks something like I became entered into the office
• but naturally it means I entered the office

This is just the normal verb choice in Persian. English uses a simple verb enter, but Persian often uses a compound expression like وارد شدن.

Yes, by itself شدم is the past of شدن and often means I became.

But in compound verbs, شدن can lose that literal become meaning and function as part of a full verb expression. Here:

• وارد شدن = to enter
• وارد اداره شدم = I entered the office

So you should learn وارد شدن as one unit, not as two separate words interpreted literally every time.

اداره usually means office, department, or administrative office, depending on context.

In this sentence, the most natural translation is:

• اداره = office

So:

• وارد اداره شدم = I entered the office

If the context were government or bureaucracy, اداره could also suggest an official department or agency.

Both can mean my colleague, but همکارم is the more natural and compact form.

The ـم attached at the end means my.

• همکار = colleague / coworker
• همکارم = my colleague

This attached pronoun is extremely common in Persian:

• دوستم = my friend
• کتابم = my book
• همکارم = my colleague

You can say همکار من, but it is usually more emphatic or contrastive, something like my colleague as opposed to someone else’s.

This is the past progressive pattern in Persian.

• داشت = was having / was in the process of
• می‌کرد = was doing

Together in this sentence:

• داشت ... صحبت می‌کرد = was talking

So:

• همکارم داشت با تلفن صحبت می‌کرد = my colleague was talking on the phone

This pattern is used for an action that was ongoing at a particular moment in the past.

That fits perfectly with the first clause:

• When I entered the office, my colleague was talking on the phone.

One event happened and interrupted or overlapped with an ongoing action.

The می‌ prefix is a very important marker in Persian. In past contexts, it often shows an ongoing, repeated, or imperfective action.

Here:

• می‌کرد comes from کردن = to do
• in صحبت می‌کرد, it helps mean was speaking / used to speak / spoke repeatedly, depending on context

In this sentence, because of داشت, the meaning is clearly progressive:

• داشت صحبت می‌کرد = was talking

So می‌ is part of how Persian builds this ongoing past meaning.

Because صحبت کردن is the normal Persian compound verb for to speak / to talk.

• صحبت = speech / conversation
• کردن = to do
• صحبت کردن = to speak / to talk

This kind of compound verb is extremely common in Persian. Instead of one simple verb, Persian often uses:

• a noun-like element + کردن

So here:

• صحبت می‌کرد = was talking

Literally, yes:

• با = with
• تلفن = telephone / phone

But in natural English translation, با تلفن صحبت کردن usually means:

• to talk on the phone
• to speak by phone

So in this sentence, با تلفن صحبت می‌کرد is best understood as:

• was talking on the phone

Not usually was talking with the phone in a literal physical sense.

Yes. You could also say:

• وقتی وارد اداره شدم، همکارم با تلفن صحبت می‌کرد.

That still often means:

• When I entered the office, my colleague was talking on the phone.

However, adding داشت makes the progressive sense more explicit. It strongly highlights that the action was in progress at that exact moment.

So:

• صحبت می‌کرد = could mean was talking or sometimes used to talk, depending on context
• داشت صحبت می‌کرد = much more clearly was talking

In standard modern Persian spelling, می‌کرد is preferred.

The small invisible separator between می and کرد is called a half-space or zero-width non-joiner. It is standard in careful writing:

• standard: می‌کرد
• less careful/less formal typing: میکرد

Both are understood, but می‌کرد is the correct standard spelling.

The same applies to many verbs:

• می‌روم
• می‌خواند
• نمی‌دانم

The comma separates the introductory time clause from the main clause:

• وقتی وارد اداره شدم، = When I entered the office,
• همکارم داشت با تلفن صحبت می‌کرد. = my colleague was talking on the phone.

It works very much like English punctuation here. In Persian, commas are often used this way to make the sentence easier to read.

Yes, Persian word order is somewhat flexible, although some versions sound more natural than others.

The given sentence is very natural:

• وقتی وارد اداره شدم، همکارم داشت با تلفن صحبت می‌کرد.

You could also put the main clause first:

• همکارم داشت با تلفن صحبت می‌کرد وقتی وارد اداره شدم.

That is understandable, but the original version sounds smoother and more standard in ordinary narration.

Also, inside the main clause, Persian often places prepositional phrases before the verb:

• با تلفن صحبت می‌کرد
• literally: with the phone talking was-doing

That is normal Persian structure, since the verb tends to come late in the clause.

A natural pronunciation in transliteration would be:

• Vaghti vâred-e edâre shodam, hamkâram dâsht bâ telefon sohbat mikard.

A few notes:

• وقتی = vaghti
• وارد = vâred
• اداره = edâre
• شدم = shodam
• همکارم = hamkâram
• داشت = dâsht
• تلفن = telefon
• صحبت می‌کرد = sohbat mikard

In natural speech, some vowels may be reduced slightly, but this transliteration is a good learner-friendly guide.

The sentence combines:

1. a completed past action
   • وارد اداره شدم = I entered the office
2. an ongoing past action
   • همکارم داشت با تلفن صحبت می‌کرد = my colleague was talking on the phone

This is a very common storytelling pattern in both Persian and English:

• When X happened, Y was already in progress.

So the sentence is a good example of how Persian expresses background action and a specific event in the past.