正确语法是这样说的：
Can you tell me by whom was the radio invented?
但是更好的（并且习惯的）说法是：
Can you tell me who invented the radio?那是不是像1L那样说的，应该变成can you tell me whom the radio was invented by?呢对，基本上 Can you tell me by whom was the radio invented? Can you tell me whom the radio was invented by? 是一样的， 但是把 by 和 whom 放在一起是比较容易理解并比较顺口的。