Relative Pronoun · اسم موصولA relative pronoun is a word like 'the ones who' that hooks a whole describing sentence onto a group. ٱلَّذِينَ means 'the ones who', and the words after it — 'have purchased error' — describe them. L5 · R13

Predicate (Khabar) · خبرThe predicate is the part that tells you something about the topic. The topic was أُو۟لَٰٓئِكَ 'those'; ٱلَّذِينَ 'the ones who…' is what is said about them — those are the ones who purchased error. L6 · R3

Verb · فعلA verb is a word for an action or happening that is always tied to a time — past, present/future, or a command. ٱشْتَرَ speaks of an action already carried out: 'bought', from the root شري: to buy, to purchase, to sell. L1 · R7

Past Tense Verb · فعل ماضٍA past-tense verb describes an action already completed — and it shows who by a small ending fastened to the verb's tail. On ٱشْتَرَوُا۟ that ending is وُا۟, telling exactly who is meant: 'bought', from the root شري: to buy, to purchase, to sell. L8 · R2

Weak Verb · فعل معتلA weak verb is a verb that carries و or ي — the 'weak' letters, which love to soften into long vowels or vanish — among its root letters. The root of ٱشْتَرَ is شري: to buy, to purchase, to sell — and its last letter is the weak ي, so the weakness sits at the very end of the root. L24 · R7

Form VIII Verb · اِفْتَعَلَA Form VIII verb tucks an extra تـ just after the first root letter. ٱشْتَرَوُا۟, from the root شري, shows that تـ after its first letter ش, marking it as Form VIII. L13 · R4

Attached Pronoun · ضمير متصلAn attached pronoun is a mini-word for 'I / you / he' that cannot stand alone — it is glued onto the end of another word, and each form carries within it exactly who is meant. وُا۟ · 'them/their' is fastened to the tail of the verb here — ٱشْتَرَوُا۟ — naming the one who did the action. L3 · R6

Doer (Fa'il) · فاعلThe doer is the one performing the action, so it stands in the nominative — the doer's form, usually shown by a ḍammah ـُ, a small curl above the last letter. The ending وُا۟ on ٱشْتَرَوُا۟ is that doer, 'they'; on this attached pronoun the shape is fixed, so no ḍammah appears, but the role it fills is the nominative one. L9 · R4

Definite Article · أل التعريفThe definite article is the prefix ٱل at the front of a noun (a naming word); it means 'the' — one specific, known one. Because the next letter, ض, is one of the fourteen 'sun-letters' — letters made in the same part of the mouth as ل itself, which swallow the ل of ٱل so it is written but not heard — the ل of the prefix melts into it and doubles it, shown by the shaddah ـّ — a small w-shaped doubling mark written above the letter: ٱلضَّلَـٰلَةَ. L2 · R9

Noun · اسمA word that accepts the prefix ٱل ('the') is a noun — a naming word. This word carries that prefix and names a thing, 'error', from the root ضلل, to go astray. L1 · R1

Feminine Noun · اسم مؤنثA feminine noun is a naming word Arabic treats as grammatically 'she', most often marked by a ة — the round 'tied tā' — at its end. ضَّلَٰلَةَ carries exactly that round ة at its end, so it is treated as feminine: '[the] astraying'. L2 · R1

Accusative · منصوبThe accusative is the ending a naming word takes when the action lands on it, usually shown by a fathah ـَ — a small slanted stroke above the last letter. ٱلضَّلَٰلَةَ ends in that fathah ـَ, marking it as what was purchased. L2 · R11

Direct Object · مفعول بهThe direct object is the thing the action lands on, and it takes the accusative — the ending shown by a fathah ـَ, a small stroke above the last letter. ٱلضَّلَٰلَةَ carries that fathah ـَ and is what they bought — the error. L9 · R3

Preposition · حرف جرThe small prefix بِ at the front of بِٱلْهُدَىٰ is a preposition — a little helper word meaning 'in/with' that relates one thing to another. A preposition 'pulls' the word that follows it into the genitive relationship — the 'of / in / with' role a word plays after such a little helper — though not every word shows that role with the same visible ending. L4 · R1

Definite Article · أل التعريفThe definite article is the prefix ٱلْ at the front of a noun (a naming word); it means 'the' — one specific, known one. The letter after it is a 'moon' letter — a letter not made in the same part of the mouth as ل — so the ل of the prefix keeps its own sound, both written and heard, resting with the sukūn ـْ (a small circle written above the letter): بِٱلْهُدَىٰ. L2 · R9

Noun · اسمA word that accepts the prefix ٱلْ ('the') is a noun — a naming word. This word carries that prefix and names a thing, 'guidance', from the root هدي, to guide. L1 · R1

Masculine Noun · اسم مذكرArabic treats every naming word as grammatically 'he' or 'she'. This word carries no feminine marker such as a ة at its end, so it falls to the default and is treated as 'he': a masculine noun. L2 · R3

Genitive · مجرورThe genitive is the ending a naming word takes after a preposition, usually shown by a kasrah ـِ — a small stroke below the last letter. هُدَىٰ stands in that genitive role after the preposition بِ 'for'; its ending rests on a final long vowel that holds the case silently, so no kasrah is written, but the role it fills is the genitive one. L2 · R12

Resumptive Particle · حرف استئنافA resumptive particle is a وَ or فَ that begins a fresh statement after a pause or a shift of topic — it starts the speech anew rather than adding one more item to a list. The prefix فَ · 'then' at the front of فَمَا opens such a fresh start. L14 · R1

Particle · حرفA particle is a small helper word of one to three letters that works like glue — it connects or adjusts other words rather than naming something or describing an action, and it can never be the one a sentence is about. مَا · 'not/what' is such a helper. L1 · R9

Negation Particle · حرف نفيA negation particle is a word meaning 'not'. مَا here negates the past-tense verb after it: 'their transaction did not profit'. L4 · R5

Verb · فعلA verb is a word for an action or happening that is always tied to a time — past, present/future, or a command. رَبِحَت speaks of an action already carried out: 'profited', from the root ربح: to profit, gain through trade. L1 · R7

Past Tense Verb · فعل ماضٍA past tense verb describes a completed action, its base form carrying no prefix. رَبِحَت has no prefix, and its ending تْ marks a 'she' doer — the transaction (a feminine noun): 'it profited'. L8 · R2

Noun · اسمA noun is a naming word for a thing. تِّجَٰرَتُ names a thing — commerce, a transaction — from the root تجر, to trade. L1 · R6

Feminine Noun · اسم مؤنثA feminine noun is a naming word Arabic treats as 'she', most often marked by a ة at its end. تِّجَٰرَتُ carries that ة (here written before the pronoun), so it is treated as feminine — which is why its verb رَبِحَت took the 'she' ending تْ. L2 · R1

Nominative · مرفوعThe nominative is the ending a naming word takes when it is the one doing the action, usually shown by a ḍammah ـُ — a small curl above the last letter. تِّجَٰرَتُ ends in that ḍammah ـُ, marking their transaction as the doer of the profiting. L2 · R10

Doer (Fa'il) · فاعلThe doer is the one performing the action, and it stands in the nominative — the doer's form, shown by a ḍammah ـُ above the last letter. تِّجَٰرَتُ carries that ḍammah ـُ and is the one that did — or here, with 'not', did not — profit. L9 · R2

Attached Pronoun · ضمير متصلAn attached pronoun is a mini-word for 'their' glued onto the end of a noun. The ending هُمْ on تِّجَـٰرَتُهُمْ stands for 'their', naming whose transaction it is. L3 · R6

Possessive (Idafa) · مضاف إليهA possessive (iḍāfah) chains an owner onto the thing owned, and the owner carries the genitive — the owner's ending, usually shown by a kasrah ـِ, a small slanted stroke below the last letter. The ending هُمْ 'their' is that owner glued onto تِّجَٰرَتُ; a pronoun like هُمْ keeps its fixed written shape, so no kasrah appears on it — the genitive is the role its owner slot carries: 'their transaction'. L5 · R5

Conjunction · حرف عطفThe prefix وَ at the front of وَمَا is a conjunction — a small joining word meaning 'and' — linking what follows to what came before; the word it joins in must stand in the same grammatical case as its partner before the joint — the same role in the sentence, even when the two words write that case with different endings. L4 · R4

Particle · حرفA particle is a small helper word of one to three letters that works like glue — it connects or adjusts other words rather than naming something or describing an action, and it can never be the one a sentence is about. مَا · 'not/what' is such a helper. L1 · R9

Negation Particle · حرف نفيA negation particle is a word meaning 'not'. مَا here negates what follows: 'they were not guided'. L4 · R5

Verb · فعلA verb is a word for an action or happening that is always tied to a time — past, present/future, or a command. كَانُ speaks of an action already carried out: 'were they', from the root كون: to be, exist, happen. L1 · R7

Past Tense Verb · فعل ماضٍA past-tense verb describes an action already completed — and it shows who by a small ending fastened to the verb's tail. On كَانُوا۟ that ending is وا۟, telling exactly who is meant: 'were they', from the root كون: to be, exist, happen. L8 · R2

Weak Verb · فعل معتلA weak verb is a verb that carries و or ي — the 'weak' letters, which love to soften into long vowels or vanish — among its root letters. The root of كَانُ is كون: to be, exist, happen — and its middle letter is the weak و, so the weakness sits in the middle of the root. L24 · R4

Kāna Verb · كان وأخواتهاكَانَ 'was' is an incomplete verb: it needs both a topic and a comment, keeping its topic nominative — the ḍammah ـُ form — while pushing its comment into the accusative, usually a fathah ـَ. Here its topic is the hidden 'they' in its ending, and its comment is 'guided', which takes that accusative ending. L18 · R3

Attached Pronoun · ضمير متصلAn attached pronoun is a mini-word glued onto the end of a verb. The ending وا۟ on كَانُوا۟ is such a suffix, standing for 'they' — the topic كَانَ speaks about. L3 · R6

Noun · اسمA noun is a word that names a person, place, thing, or idea. مُهْتَدِينَ is such a naming word: 'guided-ones', from the root هدي: to guide, show the right path. L1 · R6

Masculine Noun · اسم مذكرArabic treats every noun — every naming word — as grammatically 'he' or 'she'. Even as a plural, مُهْتَدِينَ carries no feminine marker — no ة at its end, no final ى, no اء — so it takes the default and is a masculine noun; its ending is the 'sound' plural ending Arabic reserves for masculine nouns. L2 · R3

Plural Noun · جمعA plural noun refers to three or more of something. The sound masculine plural carries its role in its ending — ـُونَ for the nominative (the 'subject form', with the ḍammah ـُ sound), ـِينَ for the accusative and genitive (the 'object' and 'of' forms); مُهْتَدِينَ closes with exactly such an ending: not one, but a whole group. L2 · R6

Accusative · منصوبThe accusative is the ending a naming word takes as the comment of كَانَ; for this kind of plural that ending is ـِينَ rather than the nominative ـُونَ. مُهْتَدِينَ carries that ـِينَ ending, marking it as the accusative comment: 'they were not guided ones'. L2 · R7

Active Participle · اسم فاعلAn active participle is a naming word built from a verb's root to name the one holding the action, and for the derived patterns it opens with مُـ. Built from the root هدي (to guide), مُهْتَدِينَ opens with مُـ and names those who are guided. L11 · R3