I myself will firmly carry out this plan. 我本人将坚决执行这个计划。
I would like to talk to the manager himself. 我要和经理本人谈一谈。
You must come in person. 必须本人来。
牛津高阶第八版
美国韦氏词典
Dictionary.com
Free Dictionary
维基百科 (自由的百科全书)