1. This is the place ___ he lived in his childhood. 此处为什么填 where , 而不填 that 呢?
2. This is just the place ___ I'm longing to visit these years. 为什么填 that , 而不填 where 呢?
3. The train was crowded and I had to get into a carriage ____ there were already seven other people. 为什么填 where , 而不是 that 呢?
4. The science of medicine , ______ progress has been very rapid recently , is perhaps the most important of all the science . 为什么填 in which , 而不填 of which 呢?
求解释, 谢谢!