In short

Prepositions are the small words that place one thing in relation to another: in the house, from the school, to the city, with a friend. Arabic needs about a dozen of them, and they are among the first words you will recognize in any text. English prepositions are famously unpredictable; the Arabic ones are unpredictable too when it comes to meaning - but their grammar is a single mechanical rule that never has an exception.

That rule is in the name. جَرّ means “pulling”, and a حَرْفُ جَرّ pulls the noun behind it into the genitive case: the noun becomes مَجْرور and normally ends in a kasra. فِي بَيْتٍ، فِي البَيْتِ، إِلَى المَدينَةِ - every one of them ends in the same sound. So this lesson is really a short vocabulary list plus one ending, wrapped in three spelling habits: three of these words are written stuck to the next word, one of them changes shape in front of الـ, and all of them take the attached pronouns you met in lesson 7.

The rule

1. The one rule: whatever follows is مَجْرور. Put a preposition in front of a noun and the noun’s final vowel becomes a kasra (point 6 has the one class of nouns that shows the same genitive with a fatḥa instead). Nothing else about the noun changes - it keeps its article or its tanwīn, it keeps its gender and number - only the case ending moves:

• indefinite, so the kasra is doubled (tanwīn kasra, ـٍ): فِي بَيْتٍ، مِنْ مَدْرَسَةٍ، مَعَ صَديقٍ
• definite with الـ, so a single kasra (ـِ): فِي البَيْتِ، مِنَ المَدْرَسَةِ، إِلَى المَدينَةِ
• definite by a pronoun suffix, same single kasra underneath the suffix: فِي بَيْتِهِ، مَعَ صَديقِنا

An adjective describing that noun follows it into the genitive, exactly as lesson 8 said it would: فِي البَيْتِ الكَبيرِ “in the big house”, فِي بَيْتٍ كَبيرٍ “in a big house”. The adjective copies both the case and the definiteness, so the two words rhyme.

This is the first place in the path where a case ending is forced on you by another word. Learn it as a reflex: preposition first, kasra second, no thinking in between.

2. The thirteen you actually need. Arabic textbooks list around seventeen حُروف جَرّ, several of which you will meet only in poetry and oaths. The working set is in the table below. A few notes worth having before you use them:

• في is both “in” and “at” - Arabic does not split them the way English does.
• بِـ is the instrument (“with a pen”), the means (“by car”), and often just “in / at” with places and prices.
• مَعَ is company - “with a friend” - and never an instrument. English “with” covers both, so this is the pair you will mix up first.
• عِنْدَ is “at someone’s place, in someone’s possession”; it is also how Arabic says “to have” (lesson 17).
• لِـ is “for, to, belonging to”; كَـ is “like, as”.

Three rows at the bottom of the table need a footnote. بَعْدَ and قَبْلَ are not really حُروف جَرّ at all - they are ظُروف, adverbials of time and place, and so are مَعَ and عِنْدَ if you are being strict. حَتَّى does belong to the traditional list of prepositions, but most of the time you will meet it in front of a verb as “until / so that” instead (lesson 33). They are all printed here for one practical reason: whatever their label, the word after them is genitive, so the learner’s job is identical. Their own behaviour - why they themselves carry a fatḥa, بَعْدَ and قَبْلَ used without a following noun - is lesson 31.

3. Three of them are prefixes: بِـ، لِـ، كَـ. These are single letters, and a single letter cannot stand alone in Arabic writing. They are joined to the following word with no space at all, and no space is an error you can see:

• بِ + قَلَمٍ = بِقَلَمٍ “with a pen”، بِ + سَيّارَةٍ = بِسَيّارَةٍ “by car”
• لِ + مُديرٍ = لِمُديرٍ “for a director”، كَ + نَهْرٍ = كَنَهْرٍ “like a river”

In front of الـ, بِـ and كَـ simply sit down on top of it and the alif stays where it is: بِالقَلَمِ، بِالسَّيّارَةِ، كَالشَّمْسِ، كَالنَّهْرِ.

لِـ is the exception: the alif of الـ disappears. لِ + الطّالِبِ is written لِلطّالِبِ - two lāms and no alif - and لِ + المُديرِ is written لِلْمُديرِ. If the noun itself begins with ل you would in principle get three lāms; Arabic writes only two: لِ + اللُّغَةِ = لِلُّغَةِ “for the language”. No other preposition does this, and it is a spelling change only - the word is pronounced exactly as you would expect.

Two smaller habits of لِـ. In front of a noun it keeps its kasra (لِطالِبٍ، لِلْمُديرِ), but in front of a pronoun it switches to a fatḥa: لَهُ، لَها، لَكُمْ - except the first person, لي. And كَـ, alone among these, is not used with a pronoun suffix in normal Modern Standard Arabic: for “like him” you say مِثْلَهُ, not كَهُ.

4. مِنْ becomes مِنَ in front of الـ. The lām of the article carries a sukūn, and the ن of مِنْ carries a sukūn, and Arabic will not pronounce two vowelless consonants in a row. The first one therefore borrows a vowel: مِنْ + البَيْتِ = مِنَ البَيْتِ، مِنَ المَدْرَسَةِ، مِنَ الصَّباحِ.

The ordinary helping vowel is a kasra, and that is what عَنْ takes: عَنِ الكِتابِ، عَنِ الرِّحْلَةِ. مِنْ is the odd one out with its fatḥa. Both are pronunciation facts that the vocalization prints; the spelling of the letters never changes.

The same collision quietly shortens the long vowel of في، عَلى and إِلى before the article - فِي البَيْتِ is said “fi-l-bayt” - but nothing at all changes in writing, so you can simply let your mouth do it.

5. Pronouns attach, exactly as in lesson 7. A preposition plus a pronoun is one word, and the pronoun is sitting in the genitive slot even though you cannot see a kasra on it: لي، لَهُ، بِهِ، مِنّي، عَنّي، مَعَها، عِنْدَهُمْ. Three seams to remember, all of them from lesson 7:

• مِنْ and عَنْ double their ن before ـي and ـنا: مِنّي، مِنّا، عَنّي، عَنّا.
• عَلى and إِلى turn their final ى back into a ي: عَلَيْهِ، عَلَيْكَ، إِلَيْها، إِلَيْنا. In the first person the two yāʾs fuse: عَلَيَّ، إِلَيَّ. And في does the same once only: فِيَّ, against plain فيهِ، فيها.
• هُ becomes هِ after a kasra or a ي: بِهِ، فيهِ، عَلَيْهِ، إِلَيْهِمْ - but مِنْهُ، عَنْهُ، مَعَهُ، عِنْدَهُ.

6. The diptote trap: some nouns take a fatḥa here, not a kasra. A small but very common class of nouns - الاسْمُ المَمْنوعُ مِنَ الصَّرْفِ, “the noun forbidden to inflect fully” - refuses tanwīn and uses a fatḥa where everything else uses a kasra. So after a preposition you get:

• إِلى مَكَّةَ، مِنْ مِصْرَ، مَعَ أَحْمَدَ، لِفاطِمَةَ - place names and personal names
• فِي مَدارِسَ، فِي مَساجِدَ، بِمَفاتيحَ - broken plurals of the مَفاعِل / مَفاعيل shape
• فِي بَيْتٍ أَخْضَرَ - the أَفْعَل colour and elative shapes
• مَعَ أَصْدِقاءَ - and nouns ending in a long ـاء, such as the أَفْعِلاء plurals

The rescue clause: put الـ on such a noun, or make it the first word of an إِضافَة, and it behaves normally again - فِي المَدارِسِ، فِي مَدارِسِ المَدينَةِ. Which nouns belong to the class, and why, is lesson 41. For now recognize the families above and do not force a kasra onto them.

7. You cannot hear it, and usually cannot see it. Two honest warnings. When a speaker stops at the end of a phrase, the final vowel is simply not pronounced - فِي البَيْتْ - so the kasra you are learning is audible only when the sentence keeps going. And ordinary Arabic writing prints no vowel marks at all: في البيت is what you will actually read. The ending is still grammatically there, and it still decides how the sentence is parsed; it is just invisible. That is what the pronunciation guide’s lesson on reading unvocalized text is for, and it is exactly why this path vocalizes everything.

8. What this lesson deliberately does not do. Which preposition a given verb demands - why it is بَحَثَ عَنْ for “look for” and حَصَلَ عَلى for “obtain” - is a different topic and has its own lesson (30); such a preposition is part of the verb’s dictionary entry, not a matter of logic. Saying “I have” with عِنْدي or لي is lesson 17. And two nouns glued into “the door of the house”, which also produces a genitive, is the إِضافَة of lesson 20 - a different mechanism with the same visible ending.

Forms & patterns

The thirteen prepositions. The last three rows are the borderline ones described above.

The three that are written joined. Note the empty cell: كَـ does not take a pronoun.

What the genitive looks like on different kinds of noun. The first six are the ones you need today - the sound feminine plural among them still takes the ordinary kasra, like everything above it; the last two are printed so you can recognize them, and they are explained in lessons 40 and 46, where the sound masculine plural and the dual are marked by a letter, not by a vowel.

The pronoun endings, first on the four that behave plainly:

And on the ones that reshape themselves at the seam:

The feminine plurals and the duals slot in where you would expect: لَكُنَّ، لَهُنَّ، لَكُما، لَهُما، مِنْهُنَّ، عَلَيْهِما، فيهِنَّ، عِنْدَهُما. Lesson 7 has the full set.

Examples

Common mistakes

• فِي البَيْتُ -> فِي البَيْتِ - the preposition forces a kasra on the noun. A ḍamma after a preposition is always wrong, however natural the dictionary form feels.
• فِي بَيْتٌ -> فِي بَيْتٍ - an indefinite noun keeps its tanwīn, but it must be the genitive tanwīn: two kasras, not two ḍammas.
• مِنْ المَدْرَسَةِ -> مِنَ المَدْرَسَةِ - the ن of مِنْ cannot keep its sukūn in front of the vowelless lām of الـ, so it takes a fatḥa. Compare عَنِ الكِتابِ, which takes a kasra instead.
• لِ الطّالِبِ / لِالطّالِبِ -> لِلطّالِبِ - لِـ is glued on, and the alif of the article drops. Two lāms, no space, no alif.
• ب القَلَمِ -> بِالقَلَمِ - the same gluing for بِـ and كَـ, though these two keep the alif. A single letter never stands alone as a word.
• إِلى مَكَّةِ -> إِلى مَكَّةَ - مَكَّة is a diptote, so its genitive is a fatḥa. Same for مِنْ مِصْرَ، مَعَ أَحْمَدَ.
• فِي المَدارِسَ -> فِي المَدارِسِ - and the reverse error: once a diptote carries الـ, it takes the ordinary kasra again.
• مِنْي / عَنْي -> مِنّي / عَنّي - both double their ن in front of ـي and ـنا.
• عَلىهِ / إِلىها -> عَلَيْهِ / إِلَيْها - the alif maqṣūra becomes a ي as soon as anything is attached behind it.
• مَعَ أَنا / لِ هُوَ -> مَعي / لَهُ - an independent pronoun never follows a preposition. The attached set of lesson 7 is the only option.

Tips

• Over-learn one reflex: preposition, then kasra. If you can do that automatically you have ninety percent of this lesson, and it will still be true at C1.
• Store each preposition inside a whole phrase - فِي البَيْتِ، مِنَ المَدْرَسَةِ، عَلَى الطّاوِلَةِ - not as a bare word with an English gloss. The ending then comes free.
• Write بِـ، لِـ، كَـ attached from the very first day. If your hand wants to leave a space, you have filed them as words instead of as letters.
• Say لِلطّالِبِ aloud as one word until the missing alif stops feeling like a typo.
• بِـ versus مَعَ is the pair to drill: بِالسِّكّينِ “with a knife” (instrument), مَعَ أَخي “with my brother” (company).
• Ignore for now which nouns are diptotes. Recognize two families - foreign or feminine proper names, and مَفاعِل-shaped plurals - and let lesson 41 do the rest.
• Do not expect a preposition to map onto one English word. Arabic verbs pick their own prepositions and you will learn those pairs verb by verb, starting in lesson 30.
• Practise the endings mid-sentence, not at the end of one. In pause the final vowel disappears, so a phrase you always say in isolation teaches you nothing about the case.