Arabic writes the definite article الـ directly onto the following noun or adjective: كتاب “a book” becomes الكتاب “the book.” The article contains an initial alif ا carrying hamzat al-waṣl in pronunciation and a lām ل. It is never separated by a space from its host.
The most important spelling principle is that the article is stable even when its pronunciation changes. Before a “sun letter,” the sound of lām assimilates to the next consonant, but the written ل remains: الشمس is pronounced ash-shams, never spelled without lām. English “the” stays a separate word and never assimilates this way, so English speakers must learn both a new spacing rule and a new spelling–sound relationship.
How the article joins
The article is a prefix, so it has no independent final position inside a normal noun phrase. Its alif stands at the right edge of the article, and its lām joins to the following letter whenever that letter permits joining. A preceding one-letter clitic can make the article appear in the middle of a larger written word.
| Build-up | Normal spelling | Position and joining |
|---|---|---|
| الـ + بيت | البيت | Article begins the written word; ل joins to ب |
| الـ + ورد | الورد | و cannot join to the following ر, but no space is inserted |
| و + الـ + كتاب | والكتاب | Article is medial within one space-delimited word; و remains visually separate from ا |
| بـ + الـ + بيت | بالبيت | ب joins into article ا; ل joins into noun ب |
| لـ + الـ + بيت | للبيت | Article alif is deleted after prepositional لـ; both lām letters remain |
البيت الكبير قريب.
al-baytu l-kabīru qarīb.
The big house is nearby.
The first article begins the utterance, so its initial vowel is heard: al-baytu. The second follows a pronounced vowel, so hamzat al-waṣl drops out in connected speech: l-kabīru. The spelling الـ is unchanged in both places.
Moon letters: lām is written and pronounced
Before a moon letter, lām keeps its sound. The moon letters are ء ب ج ح خ ع غ ف ق ك م ه و ي. In full pedagogical vocalization, lām normally carries sukūn: الْبَيْت، الْقَمَر، الْمَكْتَب.
المفتاح في الحقيبة.
al-miftāḥu fī l-ḥaqība.
The key is in the bag.
وجدت الكتاب على الطاولة.
wajadtu l-kitāba ʿalā ṭ-ṭāwila.
I found the book on the table.
In الكتاب, the moon letter ك leaves the lām audible. In الطاولة, ط is a sun letter, so the same sentence also demonstrates the other pattern.
Sun letters: pronunciation assimilates, spelling does not
The sun letters are ت ث د ذ ر ز س ش ص ض ط ظ ل ن. Before one of them, the article’s lām assimilates completely in pronunciation. The following consonant is doubled, shown by shadda in vocalized text: الشَّمْس ash-shams, الرَّجُل ar-rajul, النَّاس an-nās.
| Analytical spelling | Ordinary target | Vocalized form | Actual reading |
|---|---|---|---|
| al- + bayt | البيت | الْبَيْت | al-bayt |
| al- + shams | الشمس | الشَّمْس | ash-shams |
| al- + rajul | الرجل | الرَّجُل | ar-rajul |
| al- + layl | الليل | اللَّيْل | al-layl, with doubled l |
رأيت الشمس قبل الغروب.
raʾaytu sh-shamsa qabla l-ghurūb.
I saw the sun before sunset.
وصل القطار في الوقت المحدد.
waṣala l-qiṭāru fī l-waqti l-muḥaddad.
The train arrived at the scheduled time.
The shadda belongs only to pedagogically vocalized text; ordinary prose writes الشمس, not الشّمس unless disambiguation is useful. Adding or removing shadda does not change the base-letter skeleton used by the displayed form and its audio-ready counterpart.
A minimal definiteness contrast
The presence of attached الـ can distinguish an indefinite noun from a definite one. Arabic does not have a separately written equivalent of English “the.”
اشتريت كتابا عن تاريخ المدينة.
ishtaraytu kitāban ʿan tārīkhi l-madīna.
I bought a book about the history of the city.
وجدت الكتاب في المكتبة.
wajadtu l-kitāba fī l-maktaba.
I found the book in the library.
In the first sentence, كتابًا is indefinite and carries tanwīn in the fully vocalized form. In the second, الكتاب is definite: the article and tanwīn do not occur together. A fuller account of meaning appears in The Definite Article; the writing rule is simply that الـ attaches.
What happens after و، ف، ب، ك, and ل
The conjunctions و “and” and ف “so/then,” and the prepositions بـ “with/by/in,” كـ “like/as,” and لـ “to/for,” attach before the article. Most combinations preserve every base letter:
| Analysis | Spelling | Reading |
|---|---|---|
| wa + al-kitāb | والكتاب | wa-l-kitāb |
| fa + al-bāb | فالباب | fa-l-bāb |
| bi + al-barīd | بالبريد | bi-l-barīd |
| ka + al-baḥr | كالبحر | ka-l-baḥr |
| li + al-bayt | للبيت | li-l-bayt |
أرسلت الرسالة بالبريد.
ʾarsaltu r-risālata bi-l-barīd.
I sent the letter by mail.
هذا المفتاح للباب الخلفي.
hādhā l-miftāḥu li-l-bābi l-khalfiyy.
This key is for the back door.
The combination with لـ is exceptional in spelling: ل + الـ becomes للـ, as in للبيت. The article’s alif disappears, but its lām remains. Therefore لبيت means “for a house,” while للبيت means “for the house.”
خصصوا غرفة للضيف.
khaṣṣaṣū ghurfatan li-ḍ-ḍayf.
They set aside a room for the guest.
This example also shows sun-letter assimilation after the contracted spelling: the sequence is analyzed لـ + الـ + ضيف, written للضيف, and pronounced li-ḍ-ḍayf.
Common Mistakes
1. Separating the article from its noun
❌ ال كتاب مفيد.
Incorrect — the article must attach directly to كتاب.
✅ الكتاب مفيد.
al-kitābu mufīd.
The book is useful.
2. Dropping lām before a sun letter
❌ اشمس ساطعة في السماء.
Incorrect — assimilation affects pronunciation, not the spelling of الـ.
✅ الشمس ساطعة في السماء.
ash-shamsu sāṭiʿatun fī s-samāʾ.
The sun is bright in the sky.
3. Spacing an attached conjunction away from the article
❌ قرأت المقدمة و الخاتمة.
Incorrect — conjunction و attaches to the following word.
✅ قرأت المقدمة والخاتمة.
qaraʾtu l-muqaddimata wa-l-khātima.
I read the introduction and the conclusion.
4. Keeping article alif after prepositional لـ
❌ هذا المقعد لالمدير.
Incorrect — لـ plus الـ contracts to للـ.
✅ هذا المقعد للمدير.
hādhā l-maqʿadu li-l-mudīr.
This seat is for the director.
Key Takeaways
- Write الـ as part of its noun or adjective: الكتاب, never ال كتاب.
- Keep written lām before every sun letter: الشمس is pronounced ash-shams.
- Preceding clitics also attach: والكتاب، بالكتاب، كالكتاب.
- Only prepositional لـ + الـ deletes the article’s alif: للـ, as in للبيت.
Now practice Arabic
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Arabic →Related Topics
- Lām-Alif and Mandatory Ligature ShapesA2 — How ل plus ا forms لا and its hamzated variants without becoming an extra Arabic letter.
- Writing Attached Conjunctions, Prepositions, and PronounsA2 — How Arabic writes short conjunctions, prepositions, future سـ, and pronominal suffixes as parts of a single orthographic word.
- The Arabic Alphabet: 28 LettersA1 — Learn the names, order, core sounds, and contextual shapes of the 28 letters used in Modern Standard Arabic.
- Sun and Moon Letters with الـA2 — Read the definite article الـ accurately before sun and moon letters while keeping its spelling unchanged.
- The Definite Article الـA1 — Use the attached Arabic definite article, pronounce sun-letter assimilation, and mark definiteness across a whole noun phrase.