يمكن و ممكن ممكن ( mumken) is the correct word to use and means ( possible) يمكن ( yumken)is used for the same meaning in dialects but not in Fusha you can only use it with adding ك and so on like: يمكنكَ: (yumkinuka) its possible for you ( you can ...) singular masculine يمكنكِ ( yumkinuki) it's possible for you , singular feminine يمكنكما (yumkinukuma) dual feminine and masculine يمكنكم (yumkinukum) plural masculine يمكنكنّ ( yumkinukun-na) plural feminine ممكنك is wrong in both Fusha and dialect never used examples : . في العقد الجديد من الممكن ارسال ألف رسالة في الشهر ( fi al3aqd-iljadeed min almumkeni irsala alfa risalatin fish-shahr.) in the new contract it's possible to send thousand messages per month. يمكنك أن تقوم بتبديل القميص في المتجر لأي سبب كان.( yumkinuka an taquma bi-tabdili-lqamisi fil matjari li-ai-yi sababin kan. you can change ( it is possible for you to change) the shirt ( for another) at the store for any reason. hope I could help :)

ممكن means: is it okay to .... ممكن أن استخدم هاتفك؟ is it okay to use your phone? يمكن means: you can يمكن أن تستخدم هاتفي you can use my phone

يمكن , when you use this word alone, it means "may be" ممكن , may have two meanings: on its own, it means "That's possible" but you can use it as well in the beginning of a question, to ask for something politely, like "if you please ..." يمكنك , means "you can ...." ممكنك , actually you can't say "ممكنك " any where, i mean there is nothing called "ممكنك " Hope i could help