It was aout 600 years ago ()the first clock with a face and an ho_英语解答

It was aout 600 years ago ()the first clock with a face and an hour hand was made.
答案给的是that 为什么不能用when
或者说什么时候用when 什么时候用that
试从高中语法角度诠释

人气：254 ℃　时间：2020-02-03 20:06:57

解答

it is...that 是强调句强调句的特点是：把it is 和that去掉能还原成一个完整的句子.这个句子把it was 和that去掉可写成：The first clock with a face and an hour hand was made about 6oo years ago.因此这句话是...