第一句：这句话直接说就是 had been away FROM his hometown for twenty years
第二句：many significant advances were made in both science and philosophy IN The seventeenth century
不加介词的话很容易就看出语法错误了.
以后遇到类似的句子,可以采用这样的办法.把句子顺过来,就可以看出介词是否该放和该放哪个介词.
第一句：这句话直接说就是 had been away FROM his hometown for twenty years
第二句：many significant advances were made in both science and philosophy IN The seventeenth century
不加介词的话很容易就看出语法错误了.
以后遇到类似的句子,可以采用这样的办法.把句子顺过来,就可以看出介词是否该放和该放哪个介词.