1. Dry cough: Clear voice, no phlegm or very little phlegm, commonly seen in the early stage of upper respiratory tract infection, allergic cough or chronic pharyngitis.
2. Wet cough: the voice is relatively dull, accompanied by phlegm sounds, which can be more or less, and is mostly seen in infectious diseases such as bronchitis and pneumonia.
3. Spasmodic cough: manifested as a series of severe coughs, with red face and red ears during coughing, resembling suffocation, often seen in conditions such as pertussis and foreign body inhalation.