【正确答案】could have attended/could have been able to attend the meeting in person/by himself

【答案解析】[解析] “本来能够做某事”译作could have done sth．/could have been able to do sth.。“参加会议”泽作attend the meeting。“亲自”可译为in person或by himself。
   [点睛] 情态动词与动词的完成体连用，表示推测。