adept：熟练的，老练的，精通的 

词根词缀：ad-加强意义 +ept(-apt-)适合→能干

• deduction
• deductive
• deed
• deed poll
• deejay
• deem
• deep
• deepen
• deeply
• deep-six
• deep throat
• deer
• deerstalker
• def
• deface
• de facto
• defamatory
• defame
• default
• defeat
• defeatism
• defecate
• defect
• defection
• defective