【1】He showed me a photo in his room. 【从句】
【2】It was a photo of a famous cultural relic in Egypt.【主句】
备注:it指代the photo
The photo 【主语】// (that/which) he showed me in his room 【定语从句】
// was 【系动词】//a photo of a famous cultural relic 【表语】// in Egypt 【后置定语】
