It"s said that this kind of books _____(sell out).

It"s said that this kind of books _____(sell out).
It"s said that this kind of books _____(sell out).

It"s said that this kind of books _____(sell out).
have been sold out

have been sold out
据说这种书被卖光了。要用现在完成时，被动语态

has been sold out .已经被卖光。