1.you have no idea how busy we were these days为什么how 前不加that

1.you have no idea how busy we were these days为什么how 前不加that
1.all the machines had finished by the end of the following week为什么要用had finished不能用finishes吗,怎么看2.2.since the earth is round ,why do we not fall off的since为什么不能换成as 3.Bbelong有进行时态,有加ing吗

1.you have no idea how busy we were these days为什么how 前不加that
这是宾语从句,连接词 that ,后面加陈述句 how+疑问句,不能同时用.
2.all the machines had finished by the end of the following week为什么要用had finished不能用finishes吗,怎么看
by the end of.到..末为止,是完成时态,不是过去时态
3.since the earth is round ,why do we not fall off的since为什么不能换成as
Since 既然 As 由于 这句话意思是：既然地球是圆的,为什么我们掉不下去?
4.belong有进行时态,有加ing吗
belong 作动词,没有进行时态
加ing,是名词,所有物