eyewitness

名词 eyewitness:

1. a spectator who can describe what happened

动词 eyewitness:

1. be present at an event and see it with one's own eyes

1. An authentic account by an eyewitness.
   一份目击者的真实证言

eye.wit.ness

n.（名词）
A person who has seen someone or something and can bear witness to the fact.
见证人，目击者：曾看到某人或某事并能对事实充当证人的人