at this time用什么时间状语

at this time用什么时间状语 时间状语”this time yesterday” 前面可以加at吗? that,this开头的时间状语,何时需要用介词,何时不用?（如at that time,that morning） at that moment ；at this moment ；at this time ；at that time分别用什么时态? at this time后面用什么时态 this time在这里是做时间状语吗?this time这是个什么用法呢?My reaction was very different this time. 用所给时间状语改写下列句子I'm doing my homework now.(at this time yesterday) _________________________________________Jim takes a bath every day.(at that time)________________________________请说出为什么这样改 理由 在这段时间用in this time 还是on this time 或at this time欲速则快 今天是12月31日,假如时间状语是at the end of this year 用什么时态?2楼的,注意是有at的,是时间状语,而不是表语 He climbs the mountains once a week.(用this time yesteday作时间状语改写句子) I come here the first time.句子成分问题我知道the first time是作状语,那它是作什么状语呢?时间状语吗?如果是作时间状语的话,那换一种说法：This is the first time I come here.很明显This is the first time是主 大伙帮个忙This was a time when the two countries were at war这是个定语从句 为什么用 when ,先行词是a time 把它代入从句中,做时间状语,怎么代,时间状语放在从句中的哪个位置?具体的分析下 at this time 与 in this time 有什么区别? by the time 引导时间状语从句是现在完成时,主句用什么时态By the time you have finished this book,your meal __cold.Aget Bhas got Cwill get Dis getting. 定语从句,先行词time在后句中作时间状语时,关系词是用in which还是at which? this time 前面可以加介词吗?不是说that this 后面有时间状语就不加介词吗不是说that this 后面有时间状语就不加介词吗?但是为什么还经常说at this time？谁能给解释的明白些？ by the time of 2015,有这个时间状语的句子主句用什么时态? At this time last yea什么意思