many people don't know how to_it_French.A.say;in B.speak;with C.say;with D.speak;in

D,我们平常讲话是用 say ,比如 i said :"." / did you hear what i said?
可是如果问是用什麼语言来说,就要用speak.比如 I speak chinese（我讲中文）,在这裏,speak有一种“用...来说”的意思.所以在题中,大部分人不懂怎麼用法语来说它.强调是用法语来说,所以要用speak.it和French都是名词,所以它们之间要加介词 in .任何language前面的介词只能是"in“ ,所以是选D.
感觉我回答有点乱,要是你不是很明白可以再问我~