What kinds of accidents do you know of?为什么后面有个of?

What kinds of things happen? what kinds of还是what kind of 是what kinds of 还是which kinds of you,what,music,of,do,like,kinds what kinds of clothes begin with s what kinds of clothing begin with “t” what kinds of clothig begin witht What kinds of clothing begin with“t”? What kinds of things can youpour? What kinds of work does man do? What are three kinds of culture? what kinds of/what kind of有什么区别 what kind of 与what kinds of 有什么区别? what kind of和what kinds of的区别 what kinds of/what kind of 有什么区别 what kinds of flowers还是 what kind of flowers What ( )songs .是填kind of还是kinds of What ____books do you like?A,kind B,kind of C,kinds D,kinds of