problematic：有疑问的，未解决的，未定的 

词根词缀：pro-前 +blem扔,抛 + -atic形容词词尾

• exhausted
• exhausting
• exhaustion
• exhaustive
• exhibit
• exhibition
• exhibitionism
• exhibitionist
• exhibitor
• exhilarate
• exhort
• mousy
• mouth
• mouthpiece
• mouth-watering
• mouthy
• movable
• move
• movement
• movie
• moving
• mow
• mower
• moxie
• mozzarella