为什么特殊疑问句 what is this in english?要用is 而不是 do

为什么特殊疑问句 what is this in english?要用is 而不是 do this is an eraser in English变特殊疑问句 What is this in english?为什么要用What is what is this in English?It is a pen而不是It is a pen(英语) What is this in english? What is this in english 为什么是What is this 而不是This is what? This is my English book.改为特殊疑问句 what is this in English?同义句 请问 What is this in English? 翻译：what is this in English What is this in english翻译