خمیر دندان من تمام شده است، پس باید امروز از سوپرمارکت یک خمیر دندان جدید بخرم.

A careful transliteration is:

khamir-e dandân-e man tamâm shode ast, pas bâyad emruz az supermârket yek khamir-e dandân-e jadid bekharam.

A few quick notes:

• kh = the sound of German Bach or Scottish loch
• â = a long a sound, like in father
• In everyday speech, ast is often reduced or dropped

Because it is a compound expression made from:

• خمیر = paste
• دندان = tooth/teeth

So it literally means something like tooth paste. Persian often writes compound nouns as two separate words even when they function as one idea.

Literally, it is:

• تمام = finished, complete
• شده = become / become-done
• است = is / has

So تمام شده است literally means has become finished.

In natural English, that usually becomes:

• is finished
• has run out
• is used up

In this sentence, the natural meaning is I’ve run out of toothpaste or my toothpaste is finished.

Because تمام شدن is a very common way to express that something has been used up or has come to an end.

• تمام است = it is complete/finished
• تمام شده است = it has become finished / it has run out

For everyday things like toothpaste, soap, money, time, etc., تمام شدن sounds more natural when you mean the supply is gone.

So:

• خمیر دندان من تمام است is less natural here
• خمیر دندان من تمام شده است is the normal choice

Because possession in Persian is often shown by putting the possessor after the noun:

• خمیر دندان من = my toothpaste

This is a very normal structure in Persian.

You can also attach the possessive ending directly:

• خمیر دندانم = my toothpaste

So both are possible:

• خمیر دندان من
• خمیر دندانم

The version with من is slightly fuller and clearer; the attached version is very common in speech and writing.

پس means so, therefore, or then.

It connects the two ideas:

• My toothpaste has run out,
• so I need to buy a new one.

It is a very common connector in Persian.

Because after باید, Persian normally uses the present subjunctive form.

• باید بخرم = I must buy / I have to buy
• می‌خرم = I buy / I am buying / I will buy

So after باید, بخرم is the correct form.

This is a very common pattern:

• باید بروم = I must go
• باید بخوانم = I must read
• باید بخرم = I must buy

It is built into the verb ending.

• بخرم = I buy / that I buy / I should buy
• The ـم ending shows first person singular

So Persian often does not need a separate word for I.

If you want emphasis, you can say:

• من باید ... بخرم = I have to buy ...

But normally, the verb ending is enough.

With خریدن (to buy), Persian often uses از to show the source or place you are buying from.

So:

• از سوپرمارکت بخرم = buy from the supermarket

In natural English, we may say:

• from the supermarket
• at the supermarket

But in Persian, از is the usual preposition here.

یک literally means one, but very often it works like a/an.

So here:

• یک خمیر دندان جدید = a new toothpaste

A useful note: Persian often counts the product directly, even where English prefers something like:

• a new tube of toothpaste

So the Persian wording is normal even if the most natural English translation may add tube of.

Because adjectives usually come after the noun in Persian.

So:

• خمیر دندان جدید = new toothpaste

This is the normal Persian order:

• noun + adjective

Examples:

• کتاب جدید = new book
• خانه بزرگ = big house
• خمیر دندان جدید = new toothpaste

There is also an ezafe sound linking them, usually pronounced as -e, even though it is often not written in ordinary spelling.

So you pronounce it roughly as:

• khamir-e dandân-e jadid

Because Persian usually follows subject–object–verb order, and the verb often comes last.

In the second clause:

• باید = must
• امروز = today
• از سوپرمارکت = from the supermarket
• یک خمیر دندان جدید = a new toothpaste
• بخرم = buy

So the main action word naturally comes at the end.

That is very typical Persian sentence structure.

Formally, it is a present perfect structure.

Literally:

• has become finished

But in meaning, it often describes a present result:

• it is finished now
• it has run out now

So even though the form includes a past participle, the idea is very current and present.

That is why English might translate it as either:

• has run out or
• is finished

depending on context.

A common colloquial version would be:

خمیر دندونم تموم شده، پس باید امروز از سوپرمارکت یه خمیر دندون جدید بخرم.

Some spoken changes:

• دندان → دندون
• تمام → تموم
• یک → یه
• خمیر دندان من → خمیر دندونم
• است is often omitted in speech

This is the same meaning, just more conversational.