===== Modals =====
**What it is:** Helping verbs like **can, could, may, might, must, should, will**.  
**What it’s for:** Express ability, permission, advice, obligation, possibility.  
**Example:** “You **should** drink more water.”

===== Form =====
  * **Modal + base verb (V1)**  
    - can go, should study, must wear
  * Negative: cannot/can’t, should not/shouldn’t, must not/mustn’t
  * Questions: Can you…? Should we…?

===== Common meanings =====
  * **can:** ability/permission → “I can swim.” / “Can I sit here?”
  * **must:** strong obligation → “You must wear a helmet.”
  * **should:** advice → “You should sleep earlier.”
  * **might/may:** possibility → “It might rain.”

===== Hard words (Glossary) =====
  * *modal* /ˈməʊdl/: động từ khuyết thiếu
  * *permission* /pəˈmɪʃən/: sự cho phép
  * *obligation* /ˌɒblɪˈɡeɪʃən/: nghĩa vụ/bắt buộc
  * *possibility* /ˌpɒsəˈbɪləti/: khả năng có thể xảy ra