Be, Pe, Te, Se: ب پ ت ث

The letters ب پ ت ث share one basic joining skeleton. Their dots do the identifying work: one below, three below, two above, and three above. Learning the family as a system is faster and safer than memorizing four unrelated pictures.

In modern Iranian Persian, their usual values are b, p, t, s. The last correspondence is the surprise for English speakers who have encountered Arabic: Persian ث is pronounced s, not English th. This page teaches letter recognition and spelling; detailed articulation belongs on the consonant inventory page.

One skeleton, four dot patterns

All four letters are dual-joining: they connect to a preceding connector on the right and a following connector on the left. A font chooses the contextual shape automatically.

The letter names be, pe, te, se end in a vowel; that vowel is part of the name, not something automatically pronounced after the consonant in a word. Thus ب is named be but contributes only b in بابا.

These examples show the shared skeleton in different positions. In بابا, each alef stops the chain, so the second be begins afresh even though no space has been typed. In پدر, pe connects to dal, but dal then stops connection onward.

Be and te occur across the vocabulary

ب and ت occur freely in inherited Persian words, old borrowings, names, and modern international vocabulary. Their normal values are stable: ب = b and ت = t. Their presence by itself does not tell you where a word came from.

The written sentence is written-standard Persian. Its attached ـم in پدرم means “my”; the grammatical behavior of that ending is taught elsewhere. Here it simply shows pe initially, be as a separate word, and te initially in تاکسی.

Pe is a Persian-alphabet addition

The Arabic alphabet on which Persian writing is historically based has no native letter for p. Persian uses پ, one of its four characteristic additions, for the sound. You will see it in inherited words such as پدر and in modern loans whenever the source has p.

Calling پ “Arabic pe” is misleading: the letter belongs to the Persian alphabet and several other Arabic-script alphabets, but not to the basic Arabic alphabet. This is one visible reason Persian writing is not merely Arabic spelling with Persian words inserted.

Se is written ث but pronounced s

In normal modern Iranian Persian, ث has merged in pronunciation with س and ص. It occurs mainly in words borrowed historically from Arabic, but those words can be completely everyday. مثل “like; example” is not restricted to formal speech merely because its spelling contains ث.

Persian spelling preserves the historical letter, while Persian pronunciation supplies s. There is no pronunciation rule that lets you choose among ث، س، ص when spelling an unfamiliar /s/ word. For many Arabic-derived words, the correct letter must be learned with the word.

An Arabic quotation is a separate register and language context: a speaker trained in Arabic recitation may pronounce Arabic distinctions there. Importing Arabic th into an ordinary Persian word is not formal Persian; it is switching to an Arabic pronunciation.

Joining and word boundaries are different

Because all four letters can join on both sides, a correctly encoded word may look like one continuous stroke. Spaces still separate words, while a ZWNJ marks certain internal morphological boundaries. Neither should be inserted merely to make a letter easier to see.

The ZWNJ inside ثبت‌نام prevents full joining while keeping the compound together as one written unit. It is a boundary character, not a vowel and not one of the dots belonging to ث or ت. The spelling is normal in written-standard and formal Persian; the compound is pronounced sabt-e nâm in careful speech.

Typing accurately

On a Persian keyboard, select letters by identity, not by an approximate shape from another script layout. Count the dots after typing, especially at small screen sizes. Do not type isolated presentation forms: enter the base letters and let the rendering engine join them. Also retain Persian ک and ی in surrounding words; the Persian kaf and yeh page explains why visually similar Arabic code points can break search.

A useful proofreading method is to temporarily enlarge the text and inspect one family at a time. First locate every member of the shared skeleton; then ask whether its dots match the intended consonant. This catches errors that sounding out cannot catch: Persian ث and س sound alike, while ب and پ differ by dots that may blur at small sizes. Finally inspect real spaces and half-spaces separately. Dot identity, cursive joining, and word division are three independent layers.

The joining forms and sound values do not change between ordinary conversation and formal, academic, or literary prose. Vocabulary containing ث may be formal or everyday on its own merits. Colloquial Tehran spelling does not replace ث with س in established words.

Common Mistakes

1. Reading the skeleton but ignoring the dots

2. Giving ث its Arabic th sound in Persian

3. Breaking a joining word with an ordinary space

4. Entering the letters from left to right

5. Replacing a required half-space with a full space

Key Takeaways

• ب پ ت ث share a joining skeleton; dot number and position distinguish them.
• Their normal Iranian Persian values are b, p, t, s.
• پ is a Persian-alphabet addition, while ث survives especially in Arabic-derived spellings.
• Type base letters in right-to-left order and preserve real spaces and ZWNJ boundaries.