가게, 점 

가게 = shop, store 
채 = building counter (가게 한 채 = one store. 집 두 채 = two houses)

반찬 가게 = grocery store (슈퍼마켓)
가게를 내다, 가게를 차리다 = start a business, set up shop (내다 = put out, make (causative form of 나다). 차리다 = establish)
가게를 보다 = tend a store
가게를 열다 = start a business, open a store (for the day)
가게를 닫다 = close a business, close a store (for the day)

점 = shop, store (hanja) 
점원 = store clerk, shop assistant (-원 = worker (suffix))

백화점 = department store (백화 = a hundred [kinds of] goods)
본점/지점 = main store/branch store (본- = main. 지- = branch)
상점 = shop, store (상 = business)
서점 = bookstore (서 = writing)
식품점 = grocery store (식품 = foodstuffs/goods)
음식점 = restaurant (식당)
전문점 = specialty store (전문 = specialty)
제과점 = candy shop (제과 = confectionery)
편의점 = convenience store (편의 = convenience)

명품점 = brand, luxury store

Weak

강약 = strength and weakness
약점 = weak point (점 = point)
약(하다) = to be weak
노약자 = old and weak people (giving up your seat for people on public transport (노약자석 = seat for old and weak people))

Contract

약속(하다) = promise, appointment (속 = bind) 
약혼(하다) = mariage engagement (약혼자/약혼녀 = fiancé (male/female))
계약 = contract
예약(하다) = make a reservation (예 = before)
요약(하다) = summarize, summary

Medicine

약 = medicine
약국 = pharmacy
약사 = pharmacist
약대/약학대학 = college of pharmacology
약 = Drug
약 = Poison, poisonous drug