this kind of pen was invented (by a boy named tom)对括号部分提问() this kind of pen ()()()?

问题描述:

this kind of pen was invented (by a boy named tom)
对括号部分提问
() this kind of pen ()()()?

Who was invented by

Who was this kind of pen invented by?

By whom was this kind of pen invented?
(Whom) this kind of pen (was)(invented)(by)?