in such a long time,中的介词是in,那么at为什么不可以呢?什么时候用in和什么时候at呢

The children have been in the basement _____.A long B for longC long timeD such a long time such a long time的解释 such a long time的意思RT With such a long time,I think such a person? After a long time walk in such a hot day,he felt____and drangk a lot of water 请问为什么有so a long time而没有such a long time? Ten weeks.Such a long period of time.怎么翻译? I couldn’t possibly have finished such a long book in such a short time.我想知道,为什么用 have finished ,而不用finish? in such a long distance和on such a long distance哪个是对的? in such a long time,中的介词是in,那么at为什么不可以呢?什么时候用in和什么时候at呢 Why not have a break after studying for such a long time?（改同义句）------- ------ having a break after studying for such a long time? 英语翻译in our everyday life,some of the rubbish ,such as plastic and iron,rots away over a long periopd of time翻译away over 的意思 that 在这里是什么从句the twins had been away for such a long time that many people in the village thought they must have died . May I sit down?I’ve got pins and needles in my legs after standing here for such a long time.为什么要用after in such a short time/at that time time 什么时候和in或和at呢? so long a time为什么加a,time不可数吧,为什么还要加a?那有没有such a long time 的说法? Why did a person love someone for such a long time?怎么翻译 so many people还是such many peopleThere were( )many people at the movies ( ) we had to wait for a long time before we could get in.用 so...that 还是 such...that