强调主语:It was I who met my father at the school gate yesterday.
时间:It was yesterday that I met my father at the school gate.
地点:It was at the school gate that I met my father yesterday.
强调主语:It was I who met my father at the school gate yesterday.
时间:It was yesterday that I met my father at the school gate.
地点:It was at the school gate that I met my father yesterday.