Place Nouns: mafʿal and mafʿala

Most Arabic words come from a root of three consonants with a core meaning: ط-ب-خ is about cooking, ل-ع-ب about playing. Put the root into the pattern مَفْعَل (mafʿal) and you get the place where the action happens:

• ط-ب-خ → مطبخ (kitchen), ل-ع-ب → ملعب (stadium), ك-ت-ب → مكتب (office)
• Some take مَفْعِل (mafʿil): مسجد (mosque), منزل (house), موقف (car park)
• Some take مَفْعَلة (mafʿala): مدرسة (school), مكتبة (library), مزرعة (farm)
• Weak and doubled roots bend the pattern: ط-ي-ر → مطار (airport), ق-ه-و → مقهى (café), ح-ط-ط → محطة (station)

Add ال when you mean 'the' (في المطبخ). Leave it off before a following noun in a construct (مكتب البريد, post office) or before an indefinite adjective (منزل كبير, a big house).