concerned：(用在名词后)有关的；(用在名词前)关切的，担心的

词根词缀：concern有关 + -ed

• instruction
• instructor
• instrument
• instrumental
• instrumentalist
• instrumentation
• insubordination
• insubstantial
• insufferable
• insufficient
• insular
• insularity
• insulate
• insulating
• insulation
• insulator
• insulin
• insult
• insuperable
• insupportable
• insurance
• insurance policy
• insurant
• insure
• insurer