Grammar Particle : 못~ and ~지 못해요

Usage :

• used to show an action is not possible.
• not used in adjectives, imperative and propositive sentences.

(1) Short form

     Verbs :     못 + verb

• 못 자요     cannot sleep
• 못 팔아요     cannot sell
• 못 만들어요     cannot make

     * for 하다 verbs use : noun + 못 + 해요

• 요리하다     :     요리 못 해요     cannot cook
• 속제하다     :     속제 못 해요     cannot do homework

(2) Long form 

     Verbs :     VS + 지 못해요

• 보지 못해요     cannot see
• 가지 못해요     cannot go
• 먹지 못해요     cannot eat

    * long form of 못 can be used with adjectives to show disappointment rather than unability.

• 그 아이는 튼튼하지 못 했어요. (Too bad) That child was not healthy.
• 그 부부는 행복하지 못 했어요. (Too bad) That couple were not happy.