It is until 12 o'clock that i finished my homework为什么是that 而不是when 或/

It is until 12 o'clock that i finished my homework为什么是that 而不是when 或/ cook it until it cook it until it is OK it would be many years until Australia learnt to respect Aborigines.这句句子里是it is until那比如说it isn't until 12 o'clock that he do sth.这里为什么又是it isn't until?这样两个句型有什么区别呢?能不能说详细点,最 It is not until that She does not get up until it is nine o’clock in the evening.（中翻英） 直到,2 o clock this morning that Mike came back home直到,用it is not until还是not until.为什么? it is not until 10o'clock that he went to bed 可改为“it is until 10o'clock that he wasn't go to bed”么?就等于把否定后置,可以么? it is not until ...that...用法 It is until +从句+that造句 -----it is 9o'clock now.i must go.-----it's raining outside.( ) leave until stops.to not not to do not not 为什么选c stops The train ___at the present speed until it reachThe train ______ at the present speed until it reaches the foot of the mountain at about nine o’clock tonight.选项:a、wentb、is goingc、goesd、 will be going it is not until that 和it was not until that It is until……that It is not until ……that 分别是什么意It is until……that It is not until ……that 如果until 后面接句子用不用倒装 it is not until这个句型要倒装吗 love is not love ,until someone receives it nothiing is iearned until you can use it 'We know want is good until we have lost it It is not until that.(强调句)中not until算在句首吗,主句倒装吗?