不知道你这本书是谁编的,个人意思这就是强调句。
He never forgot the small town.
强调主语:It was he that never forgot the small town.
强调宾语:It was the small town that he never forgot.
如果出书人认为这不是强调句,那他肯定认为这里的it指的是地点呢。that 从句是定语从句,修饰town
It was the year of 1949 when People's Republic of China was founded. 1949年那一年,中华人民共和国成立了。(这个就不是强调句。因为去掉It was when这句话就不对了)
It was in the year of 1949 that People's Republic of China was founded.
就在1949年,中华人民共和国成立了。(这是强调句,可去掉it was that)
强调句中it was 后那部分,是that后面句子中的一部分。第五点不是强调句,是定语从句,that后面有从句修饰Town。