who/ that
it's.that.为强调句型.如被强调部分为“人”,可用who代替that
it's.that.正是.,就是.
就是我的好友把相册给了我.
强调句型可对除谓语以外的成分强调.如
I met my friend in the street yesterday.
It's I that/who met my friend in the street yesterday 对I 强调
It's my friend that /who I met in the street yesterday 对 my friend强调
It's in the street that I met my friend yesterday 对in the street强调
It's yesterday that I met my friend in the street.对yesterday强调