لطفا وقتی میروید، کامپیوتر را خاموش کنید.

وقتی means when. It introduces a time clause: وقتی می‌روید = when you go / when you leave.

In Persian, this kind of time clause often comes before the main action, just like in English: وقتی می‌روید، کامپیوتر را خاموش کنید. = When you leave, turn off the computer.

You may also see وقتی که instead of وقتی. The که is optional here: وقتی می‌روید and وقتی که می‌روید both work.

In Persian, the present form often appears in clauses like when you leave, even when the meaning is future relative to the moment of speaking.

So وقتی می‌روید is literally something like when you go, but in natural English the meaning is often when you leave.

This is not unusual. English also uses a present form after when: When you leave, please turn off the computer. Not When you will leave...

So Persian and English are behaving similarly here.

The ending -ید marks you plural or polite singular you.

So می‌روید can mean:

• you all go / leave
• you go / leave when speaking politely to one person

That matches the verb at the end, کنید, which also has -ید for plural/polite you.

This is very common in Persian:

• می‌روی = you go, informal singular
• می‌روید = you go, plural or polite singular

Yes. It is at least polite, and in many contexts it sounds neutral and appropriate.

The politeness comes mainly from:

• لطفا = please
• می‌روید = polite/plural you go
• کنید = polite/plural imperative

If you were speaking informally to one friend, you would more likely say: لطفا وقتی می‌روی، کامپیوتر را خاموش کن.

So the original sentence is the kind of wording you might use in an office, classroom, sign, or polite request.

را is the direct object marker. It shows that کامپیوتر is the thing being acted on.

So:

• کامپیوتر را خاموش کنید = turn off the computer

In Persian, را is commonly used when the direct object is specific or definite. Here, the speaker means a particular computer known from context, so را is natural.

Without را, the sentence would sound incomplete or less standard in this context.

It is a compound verb, written as two words.

The full dictionary form is خاموش کردن, which means to turn off or to switch off.

It is made of:

• خاموش = off / silent / extinguished
• کردن = to do, used as a light verb in many compounds

In the imperative here:

• کنید is the polite/plural command form of کردن
• so خاموش کنید = turn it off

This is very normal in Persian. Many common verbs are built this way.

In Persian, خاموش کردن is the normal verb for turning off many devices, including lights, TVs, and computers.

So:

• چراغ را خاموش کنید = turn off the light
• تلویزیون را خاموش کنید = turn off the TV
• کامپیوتر را خاموش کنید = turn off the computer

Literally, خاموش can also mean silent, not lit, or off, but with devices the meaning is straightforwardly turn off.

Not in this sentence.

می‌روید is a normal present/imperfective form meaning you go / you are going / you leave, and here it fits the time clause after وقتی.

بروید is an imperative or subjunctive-type form meaning go! or that you go. It does not fit naturally in وقتی here.

So:

• وقتی می‌روید = correct
• وقتی بروید = not natural in standard Persian for this meaning

Yes. لطفا is flexible.

The original: لطفا وقتی می‌روید، کامپیوتر را خاموش کنید.

You could also say: وقتی می‌روید، لطفا کامپیوتر را خاموش کنید.

Both are natural. Putting لطفا at the beginning is very common, especially in requests and signs.

Also, the spelling may appear as لطفاً or لطفا. Both are common; لطفاً is the more traditional spelling.

Persian usually puts the verb at the end of the clause.

So in the main clause:

• کامپیوتر را خاموش کنید literally follows the pattern computer + object marker + off + do

That is why Persian often feels like subject/object ... verb rather than English verb earlier in the sentence.

The whole sentence is structured as:

• time clause first: وقتی می‌روید
• main clause second: کامپیوتر را خاموش کنید

This is very normal Persian word order.

In standard spelling, it is usually written می‌روید with a half-space or zero-width non-joiner after می.

So the standard written form is: می‌روید

However, many people type it casually as: میروید

You should recognize both, but if you want the more standard written form, use می‌روید.

The same applies to many verbs with می:

• می‌کنم
• می‌روم
• می‌خواهید

A useful pronunciation guide is:

lotfan vaghti miravid, kāmpyuter râ khâmush konid

A few notes:

• لطفا = lotfan
• وقتی = vaghti
• می‌روید = miravid
• را is often pronounced râ
• خاموش = khâmush
• کنید = konid

In everyday speech, some sounds may become a little shorter or smoother, but this pronunciation will serve you well.

It sounds completely natural. کامپیوتر is a very common everyday word in Persian.

There is also a more Persian-based word, رایانه, but in ordinary conversation many speakers still prefer کامپیوتر.

So for a learner, کامپیوتر را خاموش کنید is perfectly natural and useful.

A natural informal singular version would be:

لطفا وقتی می‌ری، کامپیوتر را خاموش کن.

Or slightly more standard: لطفا وقتی می‌روی، کامپیوتر را خاموش کن.

Changes:

• می‌روید becomes می‌روی or colloquial می‌ری
• کنید becomes کن

So the original sentence uses the polite/plural forms, while the informal version uses singular informal forms.